France-based Ipsen SA is to advance its rare disease portfolio with the acquisition of Memo Therapeutics AG of Switzerland whose lead product is a monoclonal antibody directed against a virus that can harm patients receiving kidney transplants. The antibody, potravitug, is still in clinical development but has shown a potential to neutralise the BK polyomavirus which can lead to graft loss and the failure of a transplant. The BK virus, also known as the Human polyomavirus 1, is a member of the polyomavirus family.
Potravitug received a ‘fast track’ designation from the US Food and Drug Administration in 2023 and an orphan designation from the European Union in 2025. The candidate drug is directed against a capsid protein on the virus, thereby blocking its entry into cells.
“BK polyomavirus associated nephropathy is a significant clinical challenge in kidney transplant recipients,” said Darshana Dadhania, an associate professor of medicine at Weill Cornell Medicine, in a prepared statement, noting that the absence of a treatment targeting the virus means clinicians are forced to reduce immunosuppressive therapy. This increases the risk of graft rejection and graft loss.
In a Phase 2 study, potravitug has shown higher rates of viral load reduction in kidney transplant patients compared with a placebo, according to Ipsen.
Ipsen is pay up to €700 million to acquire Memo Therapeutics and the potravitug programme. Prior to the closing of the transaction Memo’s other assets and the employees supporting them will be spun out into an independent company to be called Memorises Bio. The transaction is expected to close during the third quarter.
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