At the end of 2017, inter partes review (IPR) proceedings for biosimilar products were on the rise. 2018 and the first half of 2019, however, have seen a dip in the number of new filings. And looking back at biosimilar IPRs that have been decided, results have been mixed. The Patent Trial and Appeal Board has denied institution in about half (47%) of its institution decisions on petitions challenging biologics-related patents. For those petitions actually reaching a Final Written Decision, the patentability of at least one claim has been upheld in just over half (53%) of the Board’s decisions. Notwithstanding the mixed results for petitioners and the recent dip in new filings discussed here, IPR remains a key battlefield for biologic innovators and biosimilar makers.
After Peaking in Fiscal 2017, Biosimilar IPR Petitions Are Declining In Number
A review of IPR filings over the last six years reveals an initial rise in petitions challenging biologics patents that peaked in fiscal year 2017, followed by a recent decline.
Figure 1
Patents, Products and Players
All types of patents protecting blockbuster biologic medicines have been subject to IPR challenges. Of the 101 petitions filed thus far, 62 challenge claims directed to methods of treatment, such as claims to dosing regimens and combination therapies. 13 petitions challenge claims to formulations of the biologics products. 13 petitions have been filed against patents covering active pharmaceutical ingredients. Biosimilar makers are also using IPRs to challenge patents that protect methods of manufacturing biologics.
Biosimilar makers continue to focus on patents covering several blockbuster biologic medicines. Indeed, 82% of the petitions filed (83) target three of the world’s best-selling biologics: Herceptin, Rituxan and Humira.
Several biosimilar makers continue to be the repeat players. Pfizer and its subsidiary Hospira have filed 31 petitions. Celltrion is second in line with 18 petitions. Coherus and Sandoz are third and fourth with 12 and 10 petitions, respectively, followed by Boehringer Ingelheim (7), Samsung (6) and Amgen (5).
Mixed Results
IPRs challenging biologic patents have met with mixed results, as shown in Figure 2 below. Institution was denied on 40 of the 85 petitions (47%) for which the Board has issued an institution decision. The rate of institution is somewhat lower than that for challenges to biotech/pharma patents in general: 59% of those petitions were instituted between September 16, 2012 and June 30, 2019.
While 1 of the instituted IPRs is still pending, Final Written Decisions have been issued in 32 cases. Of those 32 Final Written decisions, 10 upheld the patentability of all claims, 15 found all challenged claims unpatentable, and 7 produced mixed results where some claims survived while others were found unpatentable.
Figure 2
Conclusion
IPR filings by biosimilar makers are declining after reaching a peak in fiscal year 2017. As for their success, the Board has declined to institute a trial in a little over half of its institution decisions, and has upheld the patentability of one or more of the challenged claims in about half of its Final Written Decisions.
