Pharma BD Deal Intelligence

Alexion Pharmaceuticals Inc. / Portola Pharmaceuticals, Inc.

2020 · Acquisition/Merger · $1.4B · Complete

Announcement Sentiment
41
Skeptical

Alexion acquired Portola Pharmaceuticals for $18.00/share in cash, ~$1.41B total; announced May 5, 2020 and completed July 2, 2020 via tender offer (~79.7% of shares tendered) and back-end merger. The deal added Andexxa/Ondexxya (andexanet alfa), the only approved reversal agent for Factor Xa inhibitors (Eliquis, Xarelto), expanding Alexion beyond Soliris into hematology. Activist investor Elliott Management publicly criticized the deal as value-destructive. The thesis ultimately did not hold: andexanet never approached its projected blockbuster sales (peaking near $219M globally in 2024, only ~$81M of it US). Alexion itself was acquired by AstraZeneca (completed July 2021), folding Andexxa into AstraZeneca Rare Disease. The ANNEXA-I confirmatory randomized trial (2024) met its hemostasis endpoint (63.9% vs 52.4% good/excellent hemostasis) but showed materially higher thrombosis (14.6% vs 6.9%) and thrombosis-related deaths. In December 2025 AstraZeneca voluntarily withdrew Andexxa's US biologics license application effective Dec 22-23, 2025 after the FDA concluded its serious thromboembolic risks outweighed its benefit and a path from conditional to traditional approval could not be reached.

Did it work? Outcome assessment

Strategic verdict
Partially Achieved
Financial impact
Dilutive
Pipeline outcome
Mixed

Key facts

See the full interactive analysis, sources & comparables →