Full opinion text
KEVIN MCNULTY, United States District Judge These are consolidated Hatch-Waxman actions for infringement of United States Patent No. 8,822,438 ("the '438 patent") brought by Janssen Biotech, Inc.; Janssen Oncology, Inc.; Janssen Research & Development, LLC (collectively, "Janssen"); and BTG International Ltd. ("BTG"). Janssen and BTG co-own the '438 patent. The '438 patent contains twenty claims covering methods for the treatment of prostate cancer by administering various dosages of abiraterone acetate and prednisone in combination. Patent exclusivity for these medications individually is not at issue. The defendants are Amerigen Pharmaceuticals, Inc.; Amerigen Pharmaceuticals Ltd. (collectively, "Amerigen"); Amneal Pharmaceuticals LLC; Amneal Pharmaceuticals of New York, LLC (collectively, "Amneal"); Dr. Reddy's Laboratories, Inc.; Dr. Reddy's Laboratories, Ltd. (collectively "DRL"); Mylan Pharmaceuticals Inc.; Mylan, Inc. (collectively, "Mylan"); Teva Pharmaceuticals USA, Inc. ("Teva"); West-Ward Pharmaceutical Corporation, and Hikma Pharmaceuticals, LLC ("West-Ward/Hikman"); Wockhardt Bio AG; Wockhardt USA LLC; and Wockhardt Ltd. (collectively, "Wockhardt"). The defendants are generic drug companies who seek to engage in the commercial manufacture, use, offer for sale, or sale of a generic version of the plaintiffs' branded drug, ZYTIGA®. Plaintiffs allege infringement of claims 4, 8, 11, 19 and 20, all of which rely on claim 1 of the '438 patent, based on the defendants' filing of Abbreviated New Drug Applications ("ANDAs"). If defendants' ANDAs are approved, defendants will allegedly induce infringement of the asserted claims of the '438 patent under 35 U.S.C. § 271(b) and contribute to infringement of the asserted claims under 35 U.S.C. § 271(c). Defendants deny infringement and claim that the patent claims are invalid for obviousness and for lack of a written description. On November 3, 2017, defendants moved for summary judgment as to the induced and contributory infringement claims. (DE 364). The Court held a hearing on that motion on February 9, 2018. Because it appeared that there were issues of fact to be tried in any event, and that the issues on summary judgment would subsumed in those to be tried, the motion was terminated without prejudice to reassertion of all contentions therein following trial. (DE 483). Meanwhile, on January 17, 2018, the Patent Trial and Appeal Board ("PTAB"), in three inter partes proceedings, found the patent invalid. A motion for reconsideration remains pending. The Court conducted a bench trial beginning on July 23, 2018 and concluding on August 2, 2018. The parties have submitted post-trial briefing, as well as proposed findings of fact and conclusions of law. This Consolidated Opinion constitutes the Court's findings of fact and conclusions of law pursuant to Federal Rule of Civil Procedure 52(a). The findings of fact are based on the Court's observations and credibility determinations of the witnesses who testified at trial and a thorough review of all the evidence. Essentially, I rule as follows: Like the PTAB, I find that the '438 patent is invalid for obviousness. I find the patent's written description to be adequate, however. In the alternative, and to facilitate appellate review, I have ruled on the infringement issues that were tried. Assuming that the '438 patent is valid, I find based on the proposed generic labels that the ANDA defendants' marketing of abiraterone would infringe, on either an induced infringement or contributory infringement theory. I. FINDINGS OF FACT A. Procedural Background 1. On July 31, 2015, plaintiffs filed a complaint for infringement of the '438 patent based on defendants' ANDA filings, which sought approval to market generic abiraterone acetate 250 mg tablets. (Civil Action No. 15-5909, DE 1). Plaintiffs filed suit against the following ANDA defendants: a. Actavis Laboratories FL, Inc., Actavis Pharma, Inc., and Actavis, Inc. ("Actavis"), related to ANDA No. 208274; b. Amneal related to ANDA No. 208327; c. Apotex Corp. and Apotex Inc. ("Apotex") related to ANDA No. 208453; d. Citron Pharma LLC ("Citron") related to ANDA No. 208371; e. DRL related to ANDA No. 208416; f. Mylan related to ANDA No. 208446; g. Par Pharmaceutical, Inc. and Par Pharmaceutical Companies, Inc. ("Par") related to ANDA No. 208168; h. Sun Pharmaceuticals Industries, Ltd. and Sun Pharmaceuticals Industries, Inc. ("Sun") related to ANDA No. 208440; i. Teva and Teva Pharmaceuticals Industries Limited related to ANDA No. 208432; j. West-Ward/Hikma, The Arab Pharmaceutical Manufacturing Co. and Hikma Pharmaceuticals, PLC, related to ANDA No. 208339; and k. Wockhardt related to ANDA No. 208380. (DE 1). (DE 1). 2. The complaint was dismissed against certain defendants without prejudice, after they all agreed to be bound by any judgment rendered in the 15-5909 action. Those dismissed defendants are Teva Pharmaceuticals Industries Limited; Arab Pharmaceutical Manufacturing Co.; Hikma Pharmaceuticals, PLC; Actavis Pharma, Inc.; Actavis, Inc.; Par; and Citron. (DE 41, 44, 46, 103, 117). 3. On April 20, 2018, plaintiffs and Apotex entered into a license agreement for the '438 patent, and Apotex was dismissed from the action. (DE 467). 4. On September 28, 2015, plaintiffs filed a first amended complaint against Hetero USA Inc., Hetero Labs Limited Unit-V, and Hetero Labs Limited, asserting infringement of the '438 patent related to Hetero's filing of ANDA No. 208349, which sought approval to market generic abiraterone acetate 250 mg tablets. Hetero subsequently withdrew its ANDA, and on March 13, 2017, the Court entered a stipulation dismissing without prejudice plaintiffs' complaint against Hetero. (DE 308). 5. On May 2, 2016, plaintiffs filed a separate action against Amerigen, asserting infringement of the '438 patent related to Amerigen's filing of ANDA No. 208027, which also sought approval to market generic abiraterone acetate 250 mg tablets. (Civ. No. 16-02449, DE 1). This action was consolidated with the 15-5909 action on July 29, 2016 for discovery purposes. (Civ. No. 16-2449, DE 16). 6. On August 25, 2017, plaintiffs filed a separate complaint against Teva and Teva Pharmaceuticals Industries, Ltd., asserting infringement of the '438 patent related to Teva's filing of ANDA No. 210726 for approval to market generic abiraterone acetate 500 mg tablets. (Civ. No. 17-6435, DE 1). Teva Pharmaceuticals Industries, Ltd. was dismissed from this action after it agreed to be bound by any judgment. (Civ. No. 17-6435, DE 10). 7. On January 8, 2018, the 17-6435 action was consolidated with the 15-5909 action for all purposes, including trial, pursuant to Federal Rule of Civil Procedure 42(a). (Civ. No. 15-5909. DE 381). Teva's ANDA No. 208432 (at issue in the Civ. No. 15-5909 action) is substantively identical to Teva's ANDA No. 210726 (at issue in the Civ. No. 17-6435 action). B. Metastatic Castration-Resistant Prostate Cancer 8. The invention claimed in the '438 patent treats metastatic castration-resistant prostate cancer ("mCRPC") through a combination of abiraterone and prednisone. (JTX 8000). 9. The prostate is a male genitourinary organ located in the pelvis. (3T530:24-25). Prostate cancer arises when there is an uncontrollable proliferation of prostate tissue. (3T531:2-4). Metastatic prostate cancer occurs when the cancer tumor spreads from the prostate to another organ, such as the bones, liver, or lungs. (3T531:6-8). 10. Male sex hormones, called androgens, promote the growth of prostate cancer cells. (3T531:10, -22 to -24). A first-line treatment for metastatic prostate cancer is androgen deprivation therapy ("ADT"). (1T100:22-25; 3T532:19-20). Starting in the 1940s, the main treatment for prostate cancer was ADT. (1T115:23-116:1). ADT deprives cancer cells of androgens, like testosterone, through either medical or surgical castration. (1T100:24-101:3; 3T532:19-25). 11. ADT is not a cure for prostate cancer ; in most patients, ADT eventually loses effectiveness and the cancer may resume growing. (3T533:13-25). At that point the cancer is deemed castration-resistant, as that term is used in mCRPC. 12. Abiraterone, discovered in the early 1990s, is a second-line therapy. (9T1970:24). Abiraterone inhibits the 17a-hydroxylase/C17,20-lyase ("CYP17") enzyme. The CYP17 enzyme has a role in the steroid biosynthesis pathway that leads to the production of androgens, including testosterone. (1T123:13-18; 7T1434:4-21; 6T1152:5-9, 1280:1-1281:1; see PDX7.5, chart of steroid biosynthesis pathway and abiraterone inhibition, attached as an exhibit to this opinion.) 13. Dr. Johann de Bono, an oncologist and coinventor on the '438 patent, hypothesized that, while abiraterone decreased the production of androgens, it also resulted in an accumulation of "upstream" non-androgenic steroids (i.e. , those whose production branches off from the synthesis pathway before the point at which the CYP17 enzyme that is inhibited by abiraterone operates). (1T127:15-16, 128:16-129:3; 3T607:12-14). Those accumulated non-androgenic steroids would activate the androgen receptors on the prostate cancer cells, thereby reducing abiraterone's effectiveness and causing a resistance to abiraterone. (1T128:18-24; 3T607:17-20; see top horizontal row of chart, PDX7.5, attached as exhibit.) 14. To combat such resistance, Dr. de Bono hypothesized, a glucocorticoid (the family including prednisone ) could be administered to suppress those upstream steroids. (1T127:11-22, 129:8-24). C. The '438 Patent and Asserted Claims 15. On September 2, 2014, the United States Patent and Trademark Office issued the '438 patent. (JTX 8000). The named inventors of the '438 patent were Alan H. Auerbach and Arie S. Belldegrun. (DE 502, at 86 ¶ 28). Dr. de Bono was added as an inventor by order of the Court in January 2017. 16. The '438 patent, titled "Methods and Compositions for Treating Cancer," has twenty claims and is directed at methods of treating prostate cancer in humans. (JTX 8000). 17. As described in the '438 patent, it is believed that testosterone and dihydrotestosterone promote the growth of prostate cancer. (Id. at 1). The '438 patent further states that hormone therapy can be used to suppress the production or block the effects of hormones like testosterone. (Id. ). It notes that CYP17 inhibitors have been shown to be useful in the treatment of cancer, and specifically in androgen-dependent disorders like prostate cancer. (Id. at 5). 18. The '438 patent discloses such methods as the administration of a CYP17 inhibitor, like abiraterone acetate, in combination with at least one other therapeutic agent, such as an "anti-cancer agent or steroid." (Id. at 2). The '438 patent identifies prednisone as one such therapeutic agent that can be combined with abiraterone acetate. (Id. ) 19. Claim 1 of the '438 patent, the only independent claim, claims the following: 1. A method for the treatment of a prostate cancer in a human comprising administering to said human a therapeutically effective amount of abiraterone acetate or a pharmaceutically acceptable salt thereof and a therapeutically effective amount of prednisone. (Id. at 16). Claim 1 is practiced when a "therapeutically effective amount of abiraterone acetate" and a "therapeutically effective amount of prednisone" are administered to a patient with prostate cancer. (3T538:1-11). 20. Dependent claims 2-20 of the '438 patent describe additional limitations of the method, including the amount of abiraterone acetate and the amount of prednisone used, and the type of prostate cancer being treated. Plaintiffs assert infringement of claims 4, 8, 11, 19, and 20 against each defendant. 21. Those dependent claims provide as follows: a. Claim 4. The method of claim 3, wherein the therapeutically effective amount of the abiraterone acetate or pharmaceutically acceptable salt thereof is about 1000 mg/day. ... b. Claim 8. The method of claim 7, wherein the therapeutically effective amount of the prednisone is about 10 mg/day. ... c. Claim 11. The method of claim 10, comprising administering to said human about 1000 mg/day of abiraterone acetate or a pharmaceutically acceptable salt thereof and about 10 mg/day of prednisone. ... d. Claim 19. The method of claim 18, comprising administering to said human about 1000 mg/day of abiraterone acetate or a pharmaceutically acceptable salt thereof and about 10 mg/day of prednisone. ... e. Claim 20. The method of claim 17, comprising administering to said human about 1000 mg/day of abiraterone acetate or a pharmaceutically acceptable salt thereof and about 10 mg/day of prednisone. (Id. ). D. Claim Construction 22. By Order dated June 27, 2016 (DE 208), the Court adopted the parties' agreed-upon constructions (DE 502, at 89, ¶¶ 49-51) of the following undisputed '438 patent claim terms: Claim Term Joint Construction Preamble: "a method for The preamble of claim 1, on the treatment of a prostate which claims 2-20 depend, cancer in a human" is limiting and limits the claims to the treatment of a prostate cancer in a human. "refractory prostate "Prostate cancer that is not cancer" responding to an anticancer treatment or prostate cancer that is not responding sufficiently to an anti-cancer treatment. Refractory prostate cancer can also include recurring or relapsing prostate cancer." "therapeutically effective "An amount effective for amount" treating cancer." 23. On November 10, 2016, following a hearing, the Court issued its Markman patent claim construction opinion and order. (DE 239, 240, reported at BTG Int'l Ltd. v. Actavis Labs. Fl, Inc. , 2016 U.S. Dist. LEXIS 157586 (D.N.J. Nov. 10, 2016) ). The parties principally disputed the terms "treatment" and "treating." Id. at *5. 24. The Court construed the terms "treatment" and "treating" as "the eradication, removal, modification, management or control of a tumor or primary, regional, or metastatic cancer cells or tissue and the minimization or delay of the spread of cancer." Id. at *54. E. Clinical Trials and Data 25. There were a number of clinical trials of abiraterone and prednisone. The results of those trials were submitted to the United States Food and Drug Administration ("FDA") to establish the safety and efficacy of abiraterone, with the object of gaining FDA approval to market ZYTIGA®. (2T265:8-12; PDX 2.2 (Summary of Clinical Trials) ). 26. Clinical trials proceed in various phases. A Phase I trial is typically the initial drug development, and seeks to determine the safety of administering a particular drug into a human. (2T266:9-12). A Phase II clinical trial uses the findings from Phase I and extends testing to a larger patient population. Those results provide a basis for conducting a Phase III trial, which evaluates clinical efficacy and safety for regulatory approval. (2T266:13-23). 27. In April 2004, Cougar Biotechnology licensed the rights to develop abiraterone from BTG. (1T108:12-13, 230:25-231:4; 8T1817:25-1818:5). 28. In 2004 and 2005, Dr. de Bono designed the first clinical trial of abiraterone, which became known as the COU-AA-001 trial ("001 trial"). (1T108:21-23, 124:17024; PTX 13). The purpose of the 001 trial was to evaluate the safety and efficacy of abiraterone monotherapy in men with mCRPC. (1T126:16-21, 127:23-25). 29. The 001 trial was designed to proceed in two phases. (2T267:3-11). In Phase I of the 001 trial, the dose escalation phase, patients received abiraterone at doses of 250, 500, 750, 1000, or 2000 milligrams. (2T302:7-14). In the Phase II portion of the 001 study, all patients received 1000 milligrams of abiraterone acetate. (2T302:20-23). 30. For both phases of the 001 trial, Dr. de Bono proposed an "extension" phase for patients whose cancer had progressed despite the administration of abiraterone. Those patients would receive 0.5 milligrams of a glucocorticoid, dexamethasone. (1T127:11-22, 134:5-14; 2T267:12-18; PTX 11, at 4, 39-40; JTX 8086, at 1). 31. The purpose of this extension study was to evaluate Dr. de Bono's hypothesis that the addition of a glucocorticoid could suppress the upstream steroids, and thus reduce resistance to abiraterone. (1T127:11-22, 128:18-129:3). Dr. de Bono opined that prednisone, another glucocorticoid, would be just as effective as dexamethasone because all glucocorticoids would have a similar effect in terms of suppressing the upstream steroids. (1T132:13-133:20; see also 3T618:1-6; 7T1415:5-9). The study was approved by the Institutional Review Board and the Royal Marsden Cancer Research Committee. (1T142:6-8). 32. The 001 study results were published in the Journal of Clinical Oncology. Gerhardt Attard, et al., Phase I Clinical Trial of a Selective Inhibitor of CYP17, Abiraterone Acetate, Confirms that Castration-Resistant Prostate Cancer Commonly Remain Hormone Driven , 26 J. of Clinical Oncology 4563 (2008) (JTX 8083) (hereinafter referred to as "Attard 2008"); Gerhardt Attard, et al., Selective Inhibition of CYP17 with Abiraterone Acetate is Highly Active in the Treatment of Castration-Resistant Prostate Cancer , 27 J. of Clinical Oncology 3742 (2009) (JTX 8086) (hereinafter referred to as "Attard 2009"). 33. Even though the central purpose of the Phase I trial was to establish safety, the results of the trial showed that abiraterone alone had anti-tumor activity, measured by a reduction in Prostate-Specific Antigen ("PSA") levels. (1T143:21-23). The 001 trial involved 54 patients. (1T144:1). All received abiraterone. In phase I (abiraterone dose escalation), 15 of the subjects received dexamethasone as well. In phase II (administration of 1000 mg/day of abiraterone), 30 of the subjects received dexamethasone as well. (1T144:1-4). Assuming complete overlap, then, at least 30 patients received combination therapy. 34. When patients developed a resistance to abiraterone monotherapy and a glucocorticoid was added, the anti-cancer effect, measured by PSA declines of at least fifty percent, returned for 10 of the 30 combination-therapy patients in the Phase II portion of the study. (1T144:4-22; 3T588:13-24; JTX 8086). This suggested that a glutocorticoid such as prednisone, at least when administered in combination with abiraterone, has an anti-cancer effect. The suggested mechanism was the suppression of the "upstream" steroids. These upstream steroids, left unchecked, may stimulate prostate cancer growth. (Id. ; 3T604:20-24, 608:5-18, 663:12-14; 4T861:1-5; see top horizontal line of biosynthesis chart, attached.). 35. The second clinical study submitted to the FDA, the COU-AA-002 trial ("002 trial"), was similar to COU-AA-001. (2T268:12-13). The 002 trial, which was conducted in the United States, received FDA approval. (2T269:8-18). Phase I of the 002 trial tested abiraterone monotherapy to determine the best dosage. (2T268:18-19). As originally designed, the Phase II portion of the study was to consist of further abiraterone monotherapy. (2T268:18-19). However, on May 25, 2007, after the results of the 001 study suggested the effect of the glucocorticoid, the protocol of Phase II of the 002 trial was amended. (2T268:19-21, 271:8-12, 272:1). Under that amended Phase II protocol, abiraterone and prednisone would be jointly administered. (2T268:21-23). Patients received 1,000 milligrams of abiraterone and 10 milligrams of prednisone per day. (2T272:4-6). The results of 002 Phase II were published. Charles J. Ryan, et al., Phase II Study of Abiraterone Acetate in Chemotherapy-Naive Metastatic Castration-Resistant Prostate Cancer Displaying Bone Flare Discordant with Serologic Response , Clinical Cancer Research (2011). (JTX 8093). 36. A clinical study report of the 002 trial was submitted to the FDA for its consideration in approving ZYTIGA®. (2T312:16-313:2; DTX 1367). That report included a section that discussed the overall design of the study. (DTX 1367, at 19). In addressing the role of prednisone in Phase II of the 002 trial, the report noted that "all subjects were required to receive low dose glucocorticoids such as prednisone 5 mg twice daily PO or dexamethasone (0.5 mg once daily) with abiraterone acetate to better manage mineralocorticoid side effects." (Id. ). 37. The conclusion of the 002 study report provided, in full, that: • In study COU-AA-002, abiraterone acetate demonstrated encouraging antitumor activity as assessed by PSA response by PSAWG criteria; objective response by RECIST criteria; and time to PSA progression in this patient population with advanced castration-resistant prostate cancer who had prior hormonal therapies. Importantly, tumor responses to abiraterone acetate were observed in castrate patients who had prior ketoconazole medication. • Although corticosteroids were not mandated at the initiation of the study, the incidence of mineralocorticoid excess with abiraterone acetate monotherapy was of sufficient frequency to support the routine use of glucocorticosteroids. • Although the MTD of abiraterone acetate could not be definitely determined based on available data, the doses administered appear to be well tolerated with no DLTs even at 1000mg/day. The results of the study support the use of the 1000 mg daily dose of abiraterone acetate in the treatment of advanced castration-resistant prostate cancer, in view of the antitumor activity and safety observed at this dose. (DTX 1367, at 110). 38. Dr. Robert Charnas, ZYTIGA®'s global regulatory leader, suggested that because abiraterone and prednisone were tested in combination, their individual anti-cancer effects could not be determined. (2T323:25-324:8). 39. The COU-AA-003 ("003 trial") trial was another study that evaluated 1000 mg/day or abiraterone acetate in post-chemotherapy mCRPC patients. (DTX 1185). The patients in the COU-AA-003 study were allowed to be on steroids. Eighteen of forty-seven patients (38%) were on a low dose of steroids. (DTX 1185.4). PSA declines were seen in thirty-two of the forty-seven patients (68%). The results of this trial were published. Reid, et al., Significant and Sustained Antitumor Activity in Post-Docetaxel, Castration-Resistant Prostate Cancer with the CYP17 Inhibitor Abiraterone Acetate , 20 J. of Clinical Oncology 1 (2010). (DTX 1185). 40. The COU-AA-004 Phase II trial ("004 trial") used the combination of abiraterone and prednisone in post-docetaxel mCRPC patients. (2T272:7-19; 3T614:6-15). The median time to PSA progression reported in the COU-AA-003 trial and the COU-AA-004 trial was the same, approximately 5.6 months. (4T954:22-956:11). The results of the 004 trial were also published. Daniel Danila et al., Phase II Multicenter Study of Abiraterone Plus Prednisone Therapy in Patients with Docetaxel-Treated Castrate-Resistant Prostate Cancer , 28 J. of Clinical Oncology 1496, 1497 (2010). (JTX 8090). 41. The COU-AA-301 clinical trial ("301 trial") was the registration study that compared the combination of abiraterone plus prednisone to a control arm of prednisone plus a placebo. (2T276:19-277:3). The 301 trial was considered the pivotal trial showing efficacy and safety for the NDA application. (2T283:5-6). 42. Like previous trials, the coadministration arm of the 301 trial involved 1000 milligrams of abiraterone and 10 milligrams of prednisone, administered daily. (2T277:6-8). 43. Positive effects were seen in the patients receiving abiraterone plus prednisone. The Independent Data Monitoring Committee, an outside committee that evaluates patient safety throughout a clinical trial, therefore recommended that the placebo control arm of the trial be discontinued for ethical reasons. (2T277:12-278:6). All the participants were then given prednisone plus abiraterone, as opposed to a placebo. (2T277:12-17). 44. The 301 trial demonstrated that abiraterone and prednisone in combination were efficacious. (3T372:5-8). The results of the 301 trial demonstrated a four month increase in median overall survival. (2T278:9-13; 2T376:23-25). 45. The results from the 001, 002, 003, 004 and 301 trials were submitted to the FDA for review as part of the original NDA application. (2T284:9-13). No single study compared abiraterone monotherapy to abiraterone plus prednisone combination therapy. (2T293:5-7). Such a comparison by the FDA would necessarily be less direct, based on a comparison of data from different studies. (2T374:12-22). 46. The final clinical trial was the COU-AA-302 clinical trial ("302 trial"). (2T278:16). The 302 trial was the basis for a change to the indications on the ZYTIGA® label in 2018. (2T308:7-8). In the 302 trial, abiraterone plus prednisone was compared to prednisone plus a placebo. The study subjects were patients whose disease had not progressed to the point where chemotherapy was required. (2T278:18-23). The same dosages, 1000 milligrams of abiraterone and 10 milligrams of prednisone, were administered. (2T279:1-3). 47. In the 302 trial protocol, it was noted that administration of a corticosteroid "improved symptoms of fatigue and tolerability of abiraterone acetate, including symptoms of mineralocorticosteroid excess. The improved tolerability of abiraterone acetate after concomitant administration of low-dose corticosteroids was associated with suppression of ACTH and upstream adrenal steroids[.]" (DTX 1358, at 20). 48. The comparative control arm of this study, as in the 301 study, was discontinued for ethical reasons, to allow all the patients to take abiraterone plus prednisone. (2T279:8-12). The combination of abiraterone and prednisone in the 302 trial showed a sixty percent reduction in the risk of progression or death, and an overall median survival improvement of about four months. (2T279:23-280:2). F. Prior Art 49. The priority date is August 2006. (DFF at 64, ¶ 249; PFF at 154, 1764). 50. Before 2006, there was a significant divergence of opinion within the scientific community as to whether prostate cancer was androgen dependent or independent. (1T116:9-18). However, the prevailing belief was that, once the cancer resumed growing after ADT, the cancer became androgen independent. (1T116:16-18). 51. Prior to the invention described in the '438 patent, there were treatment options for prostate cancer that stopped responding to ADT, but the invention was not among them. (8T1848:18-24; see DTX 1135). 52. The relevant prior art consists of the following: a) Glenn Gerber et al., Prostate Specific Antigen for Assessing Response to Ketoconazole and Prednisone in Patients with Hormone Refractory Metastatic Prostate Cancer , 144 J. of Urology 1177 (1990) (DTX 1059) (hereinafter "Gerber 1990"); b) S.E. Barrie et al., Pharmacology of Novel Steroidal Inhibitors of Cytochrome P45017a(17a-Hydroxylase/C17-20 Lyase) , 50 J. Steroid Biochem. Molec. Biol. 267 (1994) (DTX 1062) (hereinafter "Barrie 1994"); c) Gerald Potter et al., Novel Steroidal Inhibitors of Human Cytochrome P45017a (17a-Hydroxylase-C17,20-lyase): Potential Agents for the Treatment of Prostatic Cancer, 38 J. Med. Chem. 2463 (1995) (JTX 8037) (hereinafter "Potter 1995"); d) Ian F. Tannock et al., Chemotherapy with Mitoxantrone Plus Prednisone or Prednisone Alone for Symptomatic Hormone-Resistant Prostate Cancer : A Canadian Randomized Trial with Palliative End Points , 14 J. Clin. Oncol. 1756 (1996) (DTX 1076) (hereinafter "Tannock 1996"); e) Oliver Sartor, et al., Effect of Prednisone on Prostate-Specific Antigen in Patients with Hormone-Refractory Prostate Cancer , 52(2) UROLOGY 252 (1998) (DTX 1087) (hereinafter "Sartor 1998"); f) Michael Jarman et al., The 16, 17-Douhle Bond Is Needed for Irreversible Inhibition of Human Cytochrome P45017a by Abiraterone (17-(3-Pyridyl)androsta-5,16-dien-ßbeta-ol) and Related Steroidal Inhibitors , 41 J. Med. Chem. 5375 (1998) (DTX 1085) (hereinafter "Jarman 1998"); g) F.D. Fossa et al., Flutamide Versus Prednisone in Patients with Prostate Cancer Symptomatically Progressing After Androgen-Ablative Therapy: A Phase III Study of the European Organization for Research and Treatment of Cancer Genitourinary Group , 19 J. Clin. Oncol. 62 (2001) (JTX 8048) (hereinafter "Fossa 2001"); h) Marwan Fakih et al., Glucocorticoids and Treatment of Prostate Cancer : A Preclinical and Clinical Review , 60 Urology 553 (2002) (DTX 1104) (hereinafter "Fakih 2002"); i) Katherine Harris et al., Low Dose Ketoconazole with Replacement Doses of Hydrocortisone in Patients with Progressive Androgen Independent Prostate Cancer , 168 J. Urology 542 (2002) (JTX 8053) (hereinafter "Harris 2002"); j) A. O'Donnell et al., Hormonal Impact of the 17a-Hydroxylase/C17,20-lyase Inhibitor Abiraterone Acetate (CB7630) in Patients with Prostate Cancer , 90 British J. Can. 2317 (2004) (DTX 1129) (hereinafter "O'Donnell 2004"); k) L. Vidal et al., Reversing Resistance to Targeted Therapy , 16 J. Chemo. 7 (2004) (DTX 1135) (hereinafter "Vidal 2004"); l) Gerhardt Attard et al., Selective Blockade of Androgenic Steroid Synthesis By Novel Lyase Inhibitors As A Therapeutic Strategy For Treating Metastatic Prostate Cancer , Urological Oncology (2005) (JTX 8072) (hereinafter "Attard 2005"); m) Oliver Sartor, The Continuing Challenge of Hormone-Refractory Prostate Cancer , Clinical Genitourinary Cancer (2006) (PTX 108) (hereinafter "Sartor 2006"); and n) Marc B. Garnick & Camille Motta, Androgen Deprivation Therapy, the Fu ture , Prostate Cancer Principles and Practice (2006) (DTX 1157) (hereinafter "Garnick 2006"). 53. The prior art is further summarized and discussed at Section II.A.2, infra. G. FDA Approval 54. The FDA will approve a new medication if there is substantial evidence of safety and effectiveness. (2T388:21-22). In order to obtain approval to market a new drug, a company is required to submit a New Drug Application ("NDA") to the FDA. (2T282:4-10, 387:19-388:4). An NDA application contains proposed labeling, prescribing information, animal and human studies, including phase I, II, and III clinical trials, and toxicity data. (2T282:14-283:2, 388:5-12). 55. ZYTIGA® is sold in the United States pursuant to approved NDA No. 202379. (Civ No. 15-5909, DE 502, at 90, ¶ 53). The NDA application for ZYTIGA® was submitted in December of 2010 for the use of ZYTIGA® in combination with prednisone for the treatment of men with mCRPC. (2T283:19-20, 284:18-21, 370:9-10). The NDA was specifically submitted for ZYTIGA®, and prednisone was considered a concomitant therapy. (2T411:3-5). The application received priority review as requested. (2T284:22-286:13). 56. On November 9, 2010, the FDA and Cougar Biotechnology had a "pre-NDA" meeting. (2T334:3-23, 335:9; DTX 1331). The purpose of a pre-NDA meeting is for the sponsor of a drug and the FDA to discuss the NDA; for the sponsor to inform the FDA about the NDA; and for the FDA to provide initial feedback that would aid in the NDA review process. (2T334:15-23). 57. The scientific rationale for developing abiraterone was addressed in the briefing package that was submitted to the FDA for this pre-NDA meeting. (2T336:5-7; DTX 1331, at 11-14). That scientific rationale was described as follows: Based on our understanding of abiraterone acetate's mechanism of action and as predicted by the syndrome of congenital deficiency of CYP17, we anticipated that a state of mineralocorticoid excess mediated by increased deoxycorticosteron could occur after pharmacologic inhibition of CYP17, resulting in hypertension, hypokalemia and fluid retention. Indeed, these mechanism-based toxicities were observed in Phase 1 and 2 studies. Accordingly, the Phase 1 studies were designed to allow administration of low dose corticosteroids for disease progression or for palliation of symptoms. The improved tolerability of abiraterone acetate after concomitant administration of low-dose corticosteroids was associated with suppression of ACTH and upstream adrenal steroids, including mineralocorticoids, suggesting that the combination may be better tolerated and safer regimen in this older prostate cancer patient population. Thus, the regimen of low-dose prednisone 5 mg twice a day and abiraterone acetate 1 g daily was advanced into Phase 2 and 3 testing. Prednisone was selected over other corticosteroids because it is commonly used as standard of care in combination with chemotherapy and often maintained as palliative treatment after chemotherapy is discontinued in patients with advanced metastatic prostate cancer. When abiraterone acetate was administered in a combination with oral prednisone 5 mg twice daily there appeared to be a decreased incidence and severity of mineralocorticoid based side effects, including hypertension, fluid retention and hypokalemia (Danila et al., JCO). Anti-tumor activity was observed across all patient studies as declines in prostate specific antigen levels, and in objective radiographic responses in the subset of men who had measureable disease. (DTX 1331, at 12). 58. The NDA as submitted included a "summary of clinical efficacy," i.e. , a summary of the clinical trials discussed above that established ZYTIGA®'s efficacy. (2T352:16-353:6; JTX 8187). In comparing the various clinical trials and addressing efficacy, the report noted that "[t]he totality of data from Phase 1/2 studies, Phase 2 studies, and pivotal Study COU-AA-301 consistently demonstrates the benefit of abiraterone acetate and prednisone treatment for patients with mCRPC." (JTX 8187, at 52; 2T375:8-17). 59. The summary of clinical efficacy explained the specific dosing recommendations of 1000mg/day of abiraterone and 10 mg/day of prednisone. (JTX 8187, at 54). In addressing prednisone, the recommendation provided that "concurrent treatment with prednisone" was "administered to ameliorate mineralocorticoid-related toxicity that was observed with abiraterone acetate in early Phase 1/2 studies." (Id. ). It noted that when abiraterone was administered alone, "[h]ypertension, hypokalemia, and peripheral edema were observed frequently, and were managed with the mineralocorticoid receptor antagonist eplerenone or with low-dose glucocorticosteroids." (Id. ). 60. On April 26, 2011, the FDA completed its medical review, which is the FDA's analysis and interpretation of the data presented in the clinical section of the NDA. (2T342:17-343:2; DTX 1333). In addressing the potential for overdose, drug abuse and withdrawal, the medical review included the following comment: "Abiraterone acetate is given concurrently with 10mg of prednisone once daily in order to attenuate mineralocorticoid excess resulting from reduced feedback inhibition of ACTH." (DTX 1333, at 107; 2T344:8-12). 61. The FDA approved the NDA on April 28, 2011. (2T286:19). Specifically, the FDA approved ZYTIGA® in combination with prednisone for the treatment of mCRPC. (2T393:12-17). 62. The FDA publishes Approved Drug Products with Therapeutic Equivalence Evaluations in the "Orange Book." (DE 502, at 97, ¶ 90). The FDA requires NDA holders to identify in the Orange Book "each patent that claims the drug or a method of using the drug that is the subject of the NDA ... and with respect to which a claim of patent infringement could reasonably be asserted if a person not licensed by the owner of the patent engaged in the manufacture, use, or sale of the drug product." (Id. at ¶ 91). 63. The '438 patent is listed in the Orange Book in connection with NDA No. 202379. (Id. at ¶ 92). Each defendant had knowledge of the '438 patent and its listing in the Orange Book when each respective defendant filed its Paragraph IV certification for its ANDA. (Id. at 98, ¶¶ 93-94). H. ZYTIGA Labeling 64. A medication's product label is an FDA-approved document. (2T390:2). The label contains information that the FDA believes is necessary in order for the physician to prescribe a medication properly. (2T390:2-8). The label also reflects the FDA's views about the medication and how it should be used. (2T391:14-17). 65. Physicians look to the Indications and Usage section of a label to determine why a particular therapy is being used. (3T543:8-9). The Warnings and Precautions section of a label provides information about adverse reactions that may occur when using the drug product. (2T420:4-7; PDX 406, at 4). The Dosing and Administration section of a label provides the recommended dose for each indication and subpopulation. (2T412:1-5; 3T543:18-22). 66. On April 28, 2011, the FDA approved NDA 202379, with FDA-approved labeling. (DE 502, at 90, ¶ 55). The Indications and Usage section provided that, "ZYTIGA is a CYP17 inhibitor indicated for use in combination with prednisone for the treatment of patients with metastatic castration-resistant prostate cancer who have received prior chemotherapy containing docetaxel." (Id. at 90, ¶ 55). 67. On December 12, 2012, the FDA again approved NDA 202379, with FDA-approved labeling stating in the Indications and Usage section that "ZYTIGA is a CYP17 inhibitor indicated in combination with prednisone for the treatment of patients with metastatic castration-resistant prostate cancer." (DE 502, at 90, ¶ 56). 68. On February 7, 2018, the FDA approved NDA 202379, with FDA-approved labeling stating in the Indications and Usage section that: ZYTIGA is indicated in combination with prednisone for the treatment of patients with • Metastatic castration-resistantprostate cancer (CRPC) • Metastatic high-risk castration-sensitiveprostate cancer (CSPC) (PTX 406; emphasis added). This Indications and Usage Section is representative of the Indications and Usage section on the current ZYTIGA® label. (PPF. at 14, ¶ 68). The Indications and Usage section of the label does not identify any other disease or condition, other than mCRPC and metastatic high-risk CSPC. (4T845:15-17). 69. The approved "Dosage and Administration" section of the 2018 ZYTIGA® label reads, in part: 2.1 Recommended Dose for metastatic CRPC The recommended dose of ZYTIGA is 1,000 mg (two 500 mg tablets or four 250 mg tablets) administered orally once daily in combination with prednisone 5 mg administered orally twice daily. 2.2 Recommended Dose for metastatic high-risk CSPC The recommended dose of ZYTIGA is 1,000 mg (two 500 mg tablets or four 250 mg tablets) orally once daily with prednisone 5 mg administered orally once daily. (PTX 406). These are the doses that the FDA has approved for the treatment of these diseases. (2T412:1-2). 70. Section 5 of the ZYTIGA® label, "Warnings and Precautions," warns that it may cause hypertension, hypokalemia, and fluid retention due to mineralocorticoid excess. (PDX 406, at 4). In the 2018 label, the FDA removed the following warning: "[c]o-administration of a corticosteroid suppresses adrenocorticotropic hormone (ACTH ) drive, resulting in the reduction in the incidence and severity of these adverse reactions." (2T421:13-19). 71. Section 14 of the label highlights some of the clinical studies that were completed and demonstrated efficacy. (2T415:20-22). This section specifies that "[t]he efficacy and safety of ZYTIGA with prednisone was established in three randomized, placebo-controlled, international clinical studies." (PDX 406, at 21; 2T418:1-4). I. Defendants' Labels 72. Each defendant has filed an ANDA seeking approval to market a generic form of ZYTIGA®, i.e. , abiraterone acetate tablets. (DE 502, at 91, ¶ 65). The FDA requires that a drug manufacturer, when filing for such an application, to prepare a side-by-side comparison of its proposed labels to the brand name labels. (2T398:10-13). Typically, a proposed generic's drug label is substantively the same as the approved branded drug's label. (3T393:10-13). 73. Defendants' proposed ANDA product labels recite the same mCRPC indication as the ZYTIGA® label, except that defendants' labels substitute "abiraterone acetate" for "ZYTIGA." (2T396:18-21, 407:22-24; 3T541:2-24; JTX 8011 (Amerigen's proposed label); PTX 359 (Amneal proposed label); PTX 367 (DRL); PTX 372 (Mylan); PTX 383 (Teva); PTX 393 (West-Ward/Hikman); PTX 397 (Wockhardt) ). 74. The proposed Indications and Usage sections of defendants' labels entail that they wish to market abiraterone plus prednisone for the treatment of mCRPC only. (2T408:3-5). The defendants' proposed labels do not contain the mCSPC indication that was added to the ZYTIGA® label in its 2018 version. (2T396:22-397:1). 75. The Dosage and Administration sections of defendants' labels all recommend administering 1000mg/day of abiraterone acetate, and 10mg/day of prednisone. (DE 502, at 94, ¶ 73). 76. Amerigen's, Mylan's, and West-Ward/Hikman's Dosing and Administration sections are identical to the ZYTIGA® pre-2018 labels insofar as they state that the "recommended dosage" is 1,000 milligrams of abiraterone acetate tablets administered orally once daily in combination with 10 milligrams of prednisone administered orally twice daily. (2T413:18-23; JTX 8011; PDX 393). 77. Amneal's, DRL's, Teva's, and Wockhardt's proposed Dosage and Administration sections, like the ZYTIGA® 2018 label, state the same 1000mg/ 10mg "recommended dosage," while adding the words "for mCRPC." (2T413:23-414:3). 78. The defendants' labels that are based on the ZYTIGA® 2015 label still contain the warning, dropped from the ZYTIGA® 2018 label, that "[c]o-administration of a corticosteroid suppresses adrenocorticotropic hormone (ACTH ) drive, resulting in the reduction in the incidence and severity of these adverse reactions." (2T422:16-23). The FDA has already instructed Teva to remove this language from its label. (2T424:20-21). J. ZYTIGA Marketing 79. The FDA requires pharmaceutical companies to submit marketing materials. (2T483:8-10). The materials do not have to be approved in advance, but they cannot mischaracterize a drug's indication. (2T483:23-484:1). Several of ZYTIGA®'s marketing documents discuss the role of prednisone. 80. In a marketing document related to the 2011 indication (i.e. , prior to the removal of the warning language related to the "[c]o-administration of a corticosteroid") the role of prednisone was described as reducing "the incidence and severity of mineralocorticoid-related adverse reactions" with ZYTIGA®. (DTX 1260; 2T484:7-23). 81. A ZYTIGA® brochure dedicated to explaining the role of prednisone also notes that prednisone"reduces the incidence and severity of mineralocorticoid-related adverse reactions associated with ZYTIGA." (DTX 1276; 2T488:8-22). 82. A third marketing document explaining the role of prednisone explains that prednisone lessens the system's response to a net cortisol deficit due to abiraterone. (2T489:7-12; DTX 1276). 83. Other ZYTIGA® marketing materials, however, promote ZYTIGA® in combination with prednisone solely as a means to treat prostate cancer. (PDX 424 (stating that "ZYTIGA plus prednisone achieved a statistically significant median overall survival difference"); PDT 447 (stating that "ZYTIGA plus prednisone significantly increased median radiographic progression for survival") ). II. CONCLUSIONS OF LAW The Hatch-Waxman Act strikes a balance between two competing policy interests: "(1) inducing pioneering research and development of new drugs and (2) enabling competitors to bring low-cost, generic copies of those drugs to market." Andrx Pharms., Inc. v. Biovail Corp. , 276 F.3d 1368, 1370-71 (Fed. Cir. 2002). A brand name drug manufacturer seeking FDA approval must submit an NDA that includes, among other things, a statement of the drug's components, proposed labeling describing the uses for which the drug may be marketed, and scientific data showing that the drug is safe and effective. 21 U.S.C. § 355(b)(1) ; Caraco Pharm. Labs., Ltd. v. Novo Nordisk A/S , 566 U.S. 399, 404, 132 S.Ct. 1670, 1676, 182 L.Ed.2d 678 (2012). The Hatch-Waxman Act streamlines the FDA approval process for generic manufacturers, who can "bring their products to market without submitting all of the extensive drug and clinical data ordinarily required of an NDA under 21 U.S.C. § 355(b)(1)." Takeda Pharm. U.S.A., Inc. v. W.-Ward Pharm. Corp. , 785 F.3d 625, 629 (Fed. Cir. 2015). A generic drug applicant seeking approval to market may file either an ANDA or "505(b)(2) application." 21 U.S.C. §§ 355(b)(2), (j). An ANDA allows generic drug applicants seeking approval "to rely on the safety and efficacy information for an approved drug listed in the Approved Drug Products with Therapeutic Equivalence Evaluations, or the 'Orange Book.' " Takeda , 785 F.3d at 629. After consulting the Orange Book, a generic company filing an ANDA is required to assure "the FDA that its proposed generic drug will not infringe the brand's patents." Caraco Pharm. Labs. , 566 U.S. at 406, 132 S.Ct. 1670. To achieve this, a generic manufacturer can file a "paragraph IV certification," which states that a listed patent "is invalid or will not be infringed by the manufacture, use, or sale of the [generic] drug." 21 U.S.C. § 355(j)(2)(A)(vii)(IV). The Act treats such a filing as an act of infringement, providing the brand with a right to sue immediately. See 35 U.S.C. § 271(e)(2)(A). Assuming the brand does so, the FDA may not approve the ANDA until thirty months pass, or until the court finds the patent invalid or not infringed. See 21 U.S.C. § 355(j)(5)(B)(iii). Once invalidity is asserted in a paragraph IV certification, the ANDA applicant takes on the burden of establishing it. In re Cyclobenzaprine Hydrochloride Extended-Release Capsule Patent Litig. , 676 F.3d 1063, 1078 (Fed. Cir. 2012). A patent and each of its claims are presumed to be valid, even where those claims may be dependent upon other invalid claims in the patent. 35 U.S.C. § 282(a). A party may rebut this presumption of validity only by clear and convincing evidence. Sciele Pharma Inc. v. Lupin Ltd. , 684 F.3d 1253, 1260 (Fed. Cir. 2012) (citing 35 U.S.C. § 282 ; Microsoft Corp. v. i4i Ltd. P'ship , 564 U.S. 91, 131 S.Ct. 2238, 2245, 180 L.Ed.2d 131 (2011) ). Once non-infringement is asserted in a paragraph IV certification, the patentee takes on the burden of establishing infringement by a preponderance of the evidence. See SmithKline Diagnostics, Inc. v. Helena Labs. Corp. , 859 F.2d 878, 889 (Fed. Cir. 1988) ; Kegel Co., Inc. v. AMF Bowling, Inc. , 127 F.3d 1420, 1425 (Fed. Cir. 1997). To prove infringement, the patentee must show that it is more likely than not that the proposed ANDA product would, if commercially marketed, meet the claim limitations of the patent-in-suit. See Adams Respiratory Therapeutics, Inc. v. Perrigo Co. , 616 F.3d 1283, 1287 (Fed. Cir. 2010) ; Abbott Labs. v. TorPharm, Inc. , 300 F.3d 1367, 1373 (Fed. Cir. 2002). Plaintiffs allege two kinds of infringement: "induced" and "contributory." See 35 U.S.C. § 271(b), (c). Defendants assert the defense of patent invalidity, based on lack of a sufficient written description and obviousness. I discuss the validity issues first, in section II.A. In subsection II.A.1, I conclude that the '438 patent contains an adequate description. In subsection II.A.2, I hold that the '438 patent is invalid for obviousness. In section II.B, I consider in the alternative whether, if the patent were valid, defendants' activities would infringe. In subsection II.B.1, I hold that the defendants' labels would result in induced infringement. In subsection II.B.2, I hold that there would be contributory infringement. A. Validity As a defense to infringement, defendants assert that the '438 patent is invalid for lack of a written description and for obviousness. Although asserted as a defense, the issue of patent validity is most profitably discussed in advance of the infringement contentions. The defendants prevailed on those invalidity contentions in three inter partes review proceedings ("IPR") before the PTAB. The parties state that the PTAB decisions, dated January 17, 2018, are subject to a pending motion for reconsideration. (DTX 1562 (Mylan decision); see also DE 393 (Amerigen and Wockhardt decisions).) 1. Written Description Defendants allege that the asserted claims in the '438 patent do not meet the written-description requirement of 35 U.S.C. § 112. I disagree. In pertinent part, 35 U.S.C. § 112 provides: The specification shall contain a written description of the invention and of the manner and process of making and using it, in such full, clear, concise and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor of carrying out his [or her] invention. "The purpose of this provision is to ensure that the scope of the right to exclude, as set forth in the claims, does not overreach the scope of the [invention] as described in the patent specification." Reiffin v. Microsoft Corp. , 214 F.3d 1342, 1345 (Fed. Cir. 2000) ; see also AbbVie Deutschland GmbH & Co., KG v. Janssen Biotech, Inc. , 759 F.3d 1285, 1298 (Fed. Cir. 2014). "[T]he test requires an objective inquiry into the four corners of the specification from the perspective of a person of ordinary skill in the art. Based on that inquiry, the specification must describe an invention understandable to that skilled artisan and show that the inventor actually invented the invention claimed." Ariad Pharm., Inc. v. Eli Lilly & Co. , 598 F.3d 1336, 1351 (Fed. Cir. 2010). To begin with, the '438 patent clearly sets forth the metes and bounds of the invention. It teaches the administration of a specified dosage of two specified drugs for the treatment of a specified condition in a specified, narrow class of patients, i.e. , those suffering from mCRPC. Not even minimal adjustment or experimentation is suggested; a skilled practitioner (assuming regulatory approval) would need little if any additional instruction to practice the method. In defendants' view, however, the specification is inadequate because it fails to disclose test results showing that prednisone itself provides an anti-cancer benefit. Nor, they say, does it provide sufficient information to permit a POSA to understand that both agents, abiraterone and prednisone, "treat" prostate cancer. (DBr. at 68; Def. Response at 38). These challenges fit only awkwardly within a contention that the method is not described so that a practitioner could practice it. Nevertheless, I address them. First, I find that the specification in the '438 patent sufficiently identifies prednisone as an anti-cancer agent for purposes of the 35 U.S.C. § 122 written-description requirement. As stated in my Markman opinion, that is what "treatment," as used here, means. The specification is directed to the administration of abiraterone acetate with "at least one additional therapeutic agent, such as an anti-cancer agent or a steroid." (JTX 8000). The specification defines "anti-cancer agent" as "any therapeutic agent that directly or indirectly kills cancer cells or directly or indirectly prohibits, stops or reduces the proliferation of cancer cells." (Id. at 4). The '438 patent provides a list of anti-cancer agents, including mitoxantrone, paclitaxel, docetaxel, leuprolide, goserelin, triptorelin, seocalcitol, bicalutamide, and flutamide. (Id. at 3). It further identities additional "anti-cancer" agents as "hormone ablation agents, anti-androgen agents, differentiating agents, ... antibiotic agents ... and anti-androgens." (Id. at 7). Thus, an antibiotic agent is defined as an anti-cancer agent, and prednisone is explicitly identified as an antibiotic agent. (Id. at 9). Second, the specification provides a list of steroids, including hydrocortisone, prednisone, and dexamethasone. (Id. at 3, 10). In discussing the administration of steroids, the specification provides that the "amount of the steroid administered to a mammal having cancer is an amount that is sufficient to treat the cancer whether administered alone or in combination with a 17a-hydroxylase/C17,20-lyase inhibitor." (Id. at 10). Thus, whether identified as either an "anti-cancer agent" or a "steroid," prednisone is sufficiently identified in the specification as an agent that "treats" cancer. To this extent, the patent drafter is privileged to act as his or her own lexicographer. "The specification acts as a dictionary when it expressly defines terms used in the claims or when it defines terms by implication." Novartis Corp. v. Teva Pharms. USA, Inc. , 565 F.Supp.2d 595, 604 (D.N.J. 2008) (quoting Vitronics Corp. v. Conceptronic, Inc. , 90 F.3d 1576, 1582 (Fed. Cir. 1996) ). Taking the patent's own definitions of terms as my guide, I find that the written description is adequate. 2. Obviousness Defendants allege that the combination therapy claimed in the '438 patent would already have been obvious to a person of ordinary skill in the art ("POSA") under 35 U.S.C. § 103. The burden here, as in other validity challenges, is proof by clear and convincing evidence. See pp. 87-88, supra , and cases cited. The parties agree that August 25, 2006 is the priority date for the prior art analysis. Defendants assert that, as of that date, a POSA familiar with the prior art would have been motivated to combine abiraterone acetate with prednisone for three reasons: (1) for its anti-cancer effects; (2) to mitigate abiraterone's side effects; or (3) for prednisone's palliative properties. (DBr. at 33). A patent claim is invalid as "obvious" where the "differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains." 35 U.S.C. § 103. "[O]bviousness cannot be avoided simply by a showing of some degree of unpredictability in the art so long as there was a reasonable probability of success." Pfizer, Inc. v. Apotex, Inc. , 480 F.3d 1348, 1364 (Fed. Cir. 2007) (citing In re Corkill , 771 F.2d 1496, 1500 (Fed. Cir. 1985) ("Although [the inventor] declared that it cannot be predicted how any candidate will work in a detergent composition, but that it must be tested, this does not overcome [the prior art's] teaching that hydrated zeolites will work.") ). Four factors guide the obviousness inquiry under § 103 : (1) the scope and content of the prior art; (2) the differences between the prior art and the claims at issue; (3) the level of ordinary skill in the field of the invention; and (4) objective considerations such as commercial success, long felt need, and the failure of others to develop the invention. KSR Int'l Co. v. Teleflex Inc. , 550 U.S. 398, 406, 127 S.Ct. 1727, 167 L.Ed.2d 705 (2007) (quoting Graham v. John Deere Co. , 383 U.S. 1, 17-18, 86 S.Ct. 684, 15 L.Ed.2d 545 (1966) ). The evidence at trial focused on factors 1, 2, and 4, the prior-art and objective-considerations factors. Principles specifically governing the application of those factors to a combination patent, especially a combination-therapy patent, are as follows. The novelty of a combination therapy in relation to prior art may consist in the idea of putting two known elements together. The POSA's motivation to combine prior art teachings to achieve the "claimed invention does not have to be found explicitly in the prior art references sought to be combined, but rather may be found in any number of sources, including common knowledge, the prior art as a whole, or the nature of the problem itself." Pfizer , 480 F.3d at 1362 (internal quotation and citation omitted). Accord Dystar Textilfarben GmbH v. CM. Patrick Co. , 464 F.3d 1356, 1361 (Fed. Cir. 2006) (stating that motivation to modify prior art to arrive at claimed invention "may be found in any number of sources, including common knowledge, the prior art as a whole, or the nature of the problem itself.") Thus the mix of information available to a POSA must be considered. Relevance, however, has its limits. There must be "a nexus between the claimed invention and the [objective indicia]." In re Affinity Labs of Tex., LLC , 856 F.3d 883, 901 (Fed. Cir. 2017) (quoting Ormco Corp. v. Align Tech., Inc. , 463 F.3d 1299, 1312 (Fed. Cir. 2006) ). The evidence, moreover, "must be reasonably commensurate with the scope of the claims." In re Huai-Hung Kao , 639 F.3d 1057, 1068 (Fed. Cir. 2011). To determine whether the necessary nexus exists, "[o]ur cases require consideration of whether 'the marketed product embodies the claimed features.' " ClassCo, Inc. v. Apple, Inc. , 838 F.3d 1214, 1222 (Fed. Cir. 2016) (quoting Brown & Williamson Tobacco Corp. v. Philip Morris Inc. , 229 F.3d 1120, 1130 (Fed. Cir. 2000) ); see also Pro-Mold & Tool Co. v. Great Lakes Plastics, Inc. , 75 F.3d 1568, 1573 (Fed. Cir. 1996) (noting that whether requisite nexus exists is a question of fact). In reviewing all these factors, courts use an approach that is not formulaic, but "expansive," "flexible," or "functional." KSR , 550 U.S. at 415, 127 S.Ct. 1727 ; see also Alza Corp. v. Mylan Labs., Inc. , 464 F.3d 1286, 1291 (2006) ("There is flexibility in our obviousness jurisprudence because a motivation may be found implicitly in the prior art. We do not have a rigid test that requires an actual teaching to combine."). In describing this flexible approach, the Supreme Court noted that, although "[a] factfinder should be aware, of course, of the distortion caused by hindsight bias" in evaluating obviousness, the proper approach must allow for "recourse to common sense." KSR , 550 U.S. at 421, 127 S.Ct. 1727 (citing Graham , 383 U.S. at 36, 86 S.Ct. 684 (warning against "temptation to read into the prior art the teachings of the invention in issue" and instructing courts to "guard against slipping into use of hindsight") ). The crux of defendants' argument is that the prior art would have motivated a POSA to combine abiraterone with prednisone with a reasonable expectation of success. One component of the defendants' obviousness argument is that the anti-cancer role of prednisone in actual "treatment" of mCRPC could have been anticipated. A second component of the defendants' argument, however, is that the role of prednisone in palliation or reducing side effects would also have motivated a POSA to combine it with abiraterone. Implicit in that second component is the idea that the motivation to combine therapies need not have been entirely congruent with the patented idea as conceived by the inventor. See KSR , 550 U.S. at 420, 127 S.Ct. 1727 (stating that it is error to look "only to the problem the patentee was trying to solve"); In re Kahn , 441 F.3d 977, 990 (Fed. Cir. 2006) ("[T]he skilled artisan need not be motivated to combine [the prior art] for the same reason contemplated by [the inventor]" (quoting In re Beattie , 974 F.2d 1309, 1312 (Fed. Cir. 1992) ("[T]he law does not require that the references be combined for the reasons contemplated by the inventor.") ). Thus defendants rely in part on these other effects of prednisone because those effects lent a separate impetus to the administration of abiraterone and prednisone in combination. The argument can be pushed too far; the proverbial blind pig must at least have been searching for an acorn. The case law does not suggest that obviousness must be found because an inventor, ignorant of the relevant science and considering an entirely different problem, could have stumbled on the patented method. This case, however, is close to the other end of the spectrum. The combination therapy, it is true, is patented as a "treatment." But even prednisone's effects as a palliative and a side-effect minimizer would furnish a powerful motivation to combine it with abiraterone. And the idea for such a combination, even if initially motivated only by those two effects, would have gotten the POSA to the same place. That road led straight to the practice of the patented method: the target condition would be prostate cancer ; the target population would be the subset of patients who