Pharma BD Deal Intelligence
Astellas paid $76M to fully own the Perseid Therapeutics protein-therapeutics joint venture, only to shut it down roughly two years later with no drug ever reaching market. The lead candidate, ASP2408, never advanced past Phase I for rheumatoid arthritis before Astellas folded the program into a broader 2013 R&D restructuring.
Ranks computed across 828 graded deals (Critic + Outcome Score both present).
This exercise of the buy-out option will contribute to reinforcing the drug discovery and research platform for biologics as well as enriching pipeline in…
MAXY-4 was positioned as offering 'an improved therapeutic profile' vs BMS's Orencia and belatacept, and the buyout signals Astellas's confidence in the…
Astellas has completed its purchase of all of Maxygen's equity interests in Perseid Therapeutics LLC for $76.0 million in cash.
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Astellas exercised its option to acquire Maxygen's stake in JV Perseid Therapeutics for $76M, taking full control of the protein-engineering platform and pipeline candidates. Below the typical $250M threshold but strategically notable for protein engineering consolidation.
Assessment window: 5yr post-close.
Rheumatoid arthritis is a systemic autoimmune disease characterized by T-cell-mediated synovial inflammation, joint destruction, and disability; CTLA4-Ig fusion proteins (abatacept, belatacept) selectively block T-cell co-stimulation by binding CD80/CD86. The same mechanism is used in transplant rejection prophylaxis, where belatacept (Nulojix) was FDA-approved in June 2011, just months after the Perseid buyout.
By 2011, the CTLA4-Ig class was anchored by BMS's Orencia (abatacept) — a blockbuster RA biologic with US approval in 2005 and SC formulation approval in 2011 — and BMS's belatacept (Nulojix), approved June 2011 for kidney transplant rejection prophylaxis. The broader RA biologic market was dominated by anti-TNFs (Humira, Enbrel, Remicade), with newer mechanisms like tocilizumab (Actemra) and rituximab in second-line use. Perseid's MAXY-4 was a next-generation CTLA4-Ig engineered via Maxygen's MolecularBreeding directed evolution platform to deliver an 'improved therapeutic profile' versus Orencia and belatacept. Phase 1 in RA started January 2011, triggering a $10M Maxygen milestone and likely informing Astellas's exercise of the buyout option two months later. The deal mattered because it gave Astellas full ownership of a discovery-stage protein-engineering platform plus pipeline rights — important given Astellas's otherwise limited large-molecule capabilities versus Japanese peers (Takeda, Daiichi Sankyo). Subsequent disclosures show MAXY-4 did not reach late-stage development under Astellas, illustrating the inherent risk in next-generation me-better protein candidates against entrenched incumbents.
| Deal | Year | Value | Outcome |
|---|---|---|---|
| Astellas Pharma Inc. / Maxygen, Inc. (Perseid Therapeutics stake) (this deal) | 2011 | $76M | 11 |
| Astellas Pharma Inc. / Seagen Inc. | 2009 | $4.5B | 95 |
| Astellas Pharma Inc. / Ganymed Pharmaceuticals | 2016 | $1.4B | 81 |
| Astellas Pharma Inc. / Sangamo Therapeutics, Inc. | 2026 | $50M | 63 |
| Astellas Pharma Inc. / Ogeda SA | 2017 | $850M | 59 |
| Astellas Pharma Inc. / Ocata Therapeutics, Inc. | 2015 | $379M | 41 |
| Astellas Pharma Inc. / Optimer Pharmaceuticals, Inc. | 2012 | $90M | 38 |
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