Memo Therapeutics' Potravitug Receives EU Orphan Designation for BK Polyomavirus Infection in Kidney Transplant Patients
Key Insights
The European Commission granted orphan designation to potravitug, a BK polyomavirus (search)-neutralizing antibody for treating infections in kidney transplant recipients.
The designation recognizes potravitug's potential to address a life-threatening condition affecting fewer than 5 in 10,000 people with no currently approved treatments.
Phase II SAFE KIDNEY trial data demonstrated sustained viral load reduction and resolution of BKPyV-associated nephropathy (search) in kidney transplant recipients.
Memo Therapeutics AG announced that the European Commission has granted orphan designation in the European Union for potravitug, a highly potent human BK polyomavirus (search)-neutralizing antibody for treating BKPyV infection in kidney transplant recipients. The designation recognizes both the medical plausibility of initial clinical data and that potravitug targets a life-threatening condition affecting fewer than 5 in 10,000 people.
Regulatory Benefits and Market Exclusivity
Orphan designation in the EU provides significant advantages for medicines treating rare diseases. The status confers potential 10-year market exclusivity in the EU after approval, reduced or waived European Medicines Agency fees, and access to protocol assistance. The designation was granted based on medical plausibility of initial clinical data supporting potravitug's potential efficacy in the targeted indication.
"This welcome news highlights the high unmet needs of kidney transplant recipients with BKPyV infection, for which there is currently no approved treatment, and the potential for potravitug to transform outcomes," said Erik van den Berg, CEO of Memo Therapeutics. "We will continue our discussions with regulatory authorities and planning for the initiation of a registrational trial next year."
Phase II Trial Results Support Therapeutic Potential
In November 2025, Memo Therapeutics presented data from its Phase II SAFE KIDNEY trial demonstrating sustained benefit of potravitug in kidney transplant recipients. The trial showed significant reduction in viral load and resolution of biopsy-proven BKPyV-associated nephropathy (search), supporting potravitug's role as the first targeted therapy in kidney transplant recipients to improve viral clearance and kidney allograft outcome.
The company plans to advance potravitug into Phase III clinical development in 2026. Potravitug previously received fast-track designation from the FDA in May 2023 in recognition of the high unmet medical need.
Addressing Critical Unmet Medical Need
BK polyomavirus (search) infections represent a significant challenge in kidney transplantation. More than 100,000 kidney transplants are conducted worldwide annually, with BKPyV becoming reactivated in up to 50% of these patients. Up to 70% of patients with BKPyV viremia develop BKPyV nephropathy, which significantly increases risks of kidney loss and patient death.
BKPyV infections decrease kidney functionality and longevity while reducing patient survival. Potravitug has potential to become a first-in-class BKPyV disease-modifying therapy for kidney transplant patients, with estimated market potential of up to $2 billion annually.
Company Background and Technology Platform
Memo Therapeutics is a late-stage biotech company translating unique human immune responses into superior medicines through development of best-in-class antibodies to treat viral infections and cancer. The company's proprietary DROPZYLLA® technology serves as an antibody repertoire copying engine with high-throughput screening capabilities.
The private company, located in Schlieren/Zurich, is backed by investors including Ysios Capital, Kurma Partners, Pureos Bioventures, Swisscanto, Vesalius Biocapital and Adjuvant Capital. Alongside potravitug, the company focuses on discovering novel antibody-target pairs in oncology.