Ipsen Acquires Memo Therapeutics for €200M, Up to €700M with Milestones
French pharmaceutical company Ipsen announced on Wednesday the acquisition of Swiss biotech firm Memo Therapeutics AG to bolster its rare disease portfolio. The deal focuses on potravitug, a Phase II monoclonal antibody targeting the BK polyomavirus in kidney transplant patients.
A Structured Acquisition in Two Stages for up to €700M
Ipsen will pay €200M at the transaction's close to acquire all shares of Memo Therapeutics AG on a cash-free and debt-free basis. Additional deferred payments linked to development milestones, regulatory approvals, and sales figures could bring the total compensation to over €700M. The closure is expected in the third quarter of 2026, subject to customary closing conditions. Prior to the deal's conclusion, Memo Therapeutics' assets and employees not related to potravitug will be transferred to a new entity, Memorises Bio, retained by Memo's shareholders. This restructuring includes the Dropzylla discovery platform and a collaboration with CSL on a recombinant polyimmunoglobulin program. Ipsen notes that the impact of this midstage acquisition is incorporated in its financial forecasts for the current year.
Potravitug in Advanced Phase II with Established Efficacy Results
Potravitug received fast-track designation from the FDA in May 2023 and orphan drug designation from the European Medicines Agency in December 2025. The Phase II SAFE Kidney II trial, the largest placebo-controlled trial in kidney transplant patients with BK polyomavirus-associated nephropathy (BKPyVAN), included 95 patients across 22 sites in the US. The primary endpoint was met: a ≥ 1-log10 viral reduction or undetectable levels by day 20 were observed at higher rates in the potravitug group than in the placebo. By week 38, 24.4% of treated patients achieved undetectable BKPyV-DNAemia compared to 13.0% in the placebo group. Reductions > 2-log10 occurred in 40.3% versus 24.7% respectively. Biopsy-proven nephropathy declined from 51.2% to 31.6% in the potravitug group, with no change observed under placebo. The tolerance profile was favorable, with no serious adverse events related to treatment reported. A Phase II/III trial, SAFE Kidney III, is set to begin later in 2026.
A Major Target Population Without Approved Targeted Treatment
Approximately 90% of kidney transplant recipients are seropositive for the BK polyomavirus. About 30% of these patients exhibit a high viral load in the first year post-transplant, indicating reactivation. Over 100,000 kidney transplants are performed annually worldwide, with more than 28,000 in the US, and over 90,000 patients awaiting a transplant. Currently, no approved targeted therapy exists for this infection; management relies on balancing reduced immunosuppression (risking rejection) and viral control, a challenging clinical trade-off.
