The US Food and Drug Administration (FDA) has granted a novel vaccine orphan designation as a treatment for multiple myeloma (MM).
The vaccine, known as ImMucin, targets the signal peptide domain of the MUC1 tumor antigen.
ImMucin works by “teaching” the immune system to identify and destroy cells that display a short, specific, 21-mer portion from MUC1, which appears on 90% of all cancer cells but not in patients’ blood.
Results of a phase 1/2 trial suggested that ImMucin was safe and active in MM patients. The trial included 15 MUC1-positive patients who had residual or biochemically progressive disease after autologous stem cell transplant.
The patients received 6 or 12 bi-weekly intradermal doses of ImMucin co-administered with human granulocyte-macrophage colony-stimulating factor.
The researchers said the vaccine was well-tolerated, as all adverse events were temporary, grade 1-2 in nature, and resolved spontaneously.
There was a significant decrease in soluble MUC1 levels in 9 patients, and 11 patients had stable disease or clinical improvement that persisted for 17.5 months to more than 41.3 months.
A follow-on study (which is ongoing) in patients who responded to ImMucin has shown that some patients can go more than 4 years without requiring any further treatment for their disease.
ImMucin is under development by Vaxil Biotherapeutics Ltd. The vaccine also has orphan designation as a treatment for MM in the European Union.
About orphan designation
The FDA grants orphan designation to encourage companies to develop therapies for diseases that affect fewer than 200,000 individuals in the US.
Orphan designation provides a company with research and development tax credits, an opportunity to obtain grant funding, exemption from FDA application fees, and other benefits.
If the FDA approves ImMucin to treat patients with MM, orphan designation will provide Vaxil Biotherapeutics with 7 years of marketing exclusivity in the US.
