The immune systems of individuals undergoing potentially life-saving transplantations – the two most common types of which are allogeneic hematopoietic stem cell transplant (HSCT) and solid organ transplants (SOT) – are suppressed or eliminated to prevent rejection of the transplanted cells or organs, leaving the patient highly prone to devastating viral infections or diseases, which can cause end-organ damage and mortality.
Allogeneic HSCT conditioning regimens often require the complete elimination of a patient’s own stem cells leaving patients without a functioning immune system and in a severely immunocompromised state post HSCT. For 90% of allogeneic HSCT patients, their suppressed immune system allows viruses that were previously in a latent state to reactivate, with more than 60% of HSCT patients experiencing reactivation of more than one potentially fatal virus.
Currently, there are no approved therapies for most viral infections in the post-transplant setting, with the standard of care treatments having limited efficacy and associated with significant toxicity.
Posoleucel is designed to play an important role in providing bridging immunity between conditioning and reconstitution of their immune systems. Restoring immunity during this time of severe immune compromise, posoleucel may substantially reduce or prevent virus-associated morbidity and mortality, and dramatically improve patient outcomes.
Posoleucel has the potential to fundamentally transform care for transplant patients, as well as individuals who are at high risk for opportunistic viral infections by reducing or preventing disease morbidity and dramatically improving patient outcomes.
Posoleucel was evaluated in a Phase 2 open label proof-of-concept study, in which 58 allogeneic HSCT patients with treatment-refractory infections were treated with posoleucel. 93% of patients who received posoleucel demonstrated a predefined clinical response. Treatment with posoleucel was generally well-tolerated. These interim trial results were published in the Journal of Clinical Oncology in August 2017.
Posoleucel has been granted PRIority MEdicines (PRIME) and Orphan Drug (ODD) designations from the EMA and Regenerative Medicine Advanced Therapy (RMAT) designation from the U.S. Food and Drug Administration (FDA).
To explore the clinical benefits of posoleucel, we plan to initiate a total of six Phase 3 pivotal and Phase 2 proof-of-concept trials in immunocompromised HSCT and SOT patients for the treatment and prevention of life-threatening viral diseases in children and/or adults.
Learn more about posoleucel clinical trials here.