AlloVir has generated early evidence its lead prospect works in solid organ transplant patients, reporting phase 2 data that suggest it has a shot at expanding beyond its initial focus on stem cell transplants.
The Massachusetts-based biotech has already taken posoleucel, an off-the-shelf, multi-virus specific T-cell therapy, into phase 3 trials in three indications for allogeneic hematopoietic stem cell transplant patients. In parallel, AlloVir has laid the groundwork for an expansion into the solid organ field by assessing the ability of posoleucel to treat a virus called BK viremia (BKV) in adult kidney transplant recipients.
Once a person is infected with BKV, one of six pathogens targeted by posoleucel, the virus stays in the body but doesn’t typically cause problems. However, the drugs taken to prevent organ rejection give the virus a chance to proliferate and, given the lack of effective therapies, cause negative health outcomes.
The phase 2 trial provides early evidence that posoleucel may improve outcomes in BKV patients. After 24 weeks, 39% of recipients of posoleucel had a one log or greater reduction in viral load, compared to 14% of people on placebo. Posoleucel appears to be most effective when given biweekly and in people with a high initial viral load, with 75% of patients in that small subgroup having a one-log reduction.
With posoleucel outperforming placebo on other viral load measures, and adverse events reports being consistent with the underlying patient population and background immunosuppression, AlloVir and its collaborators think the cell therapy has a shot at targeting the solid transplant space.
“The safety profile of posoleucel and its antiviral activity, which is amplified in high viral load patients who have the greatest unmet need, suggest it could potentially offer a transformative treatment option for kidney transplant patients with BK viremia,” Brigham and Women’s Hospital’s Anil Chandraker, M.D., the principal investigator of the posoleucel BKV treatment study, said in a statement.
AlloVir plans to work with regulatory authorities and transplant specialists to formulate a plan for further development in kidney transplant patients and potentially in recipients of other solid organs.