PT-112, an investigational small molecule that promotes cancer cell death, has been designated an orphan drug by the U.S. Food and Drug Administration (FDA) for the treatment of multiple myeloma, announced Phosplatin Therapeutics, which is developing the potential therapy.
Orphan drug status is expected to support and expedite the clinical development and regulatory review of PT-112.
The medicine is being tested in a Phase 1/2 trial (NCT03288480) for relapsed or refractory multiple myeloma. The first patients already have been enrolled, the company said in the announcement, and is recruiting more participants.
Led by P. Leif Bergsagel, MD, the David F. and Margaret T. Grohne Research Professor in Therapeutics for Cancer Research at Mayo Clinic, the open-label trial consists of two parts.
In the first part, patients will receive increasing doses of PT-112, to assess safety and toxicity measures. This will allow researchers to determine the most effective dose with fewer side effects. Then, in the second part, a group of 14 patients will receive the optimal dose to further evaluate its safety, effectiveness, and tolerability profile.
PT-112 is a novel small molecule conjugate of pyrophosphate and platinum designed to overcome the toxicity and resistance of standard chemotherapeutic agents. It triggers cancer cell death, which releases particles that recruit and activate T-cells against tumors.
PT-112 is in a Phase 1 study (NCT02266745) for the treatment of several types of solid tumors. Preliminary results show the medicine induces beneficial effects across a range of dose levels in patients who have received multiple prior therapies.
The therapy also has affinity for specific compartments within the bone, which, together with preclinical data showing that PT-112 reduces cancer cell activity in myeloma mouse models, suggests the drug might effectively treat blood cancers.
Findings were presented in a poster, “Translational Research of PT-112, a Clinical Agent in Advanced Phase I Development: Evident Bone Tropism, Synergy in Vitro with Bortezomib and Lenalidomide, and Potent Efficacy in the Vk*MYC Mouse Model of Multiple Myeloma,” during the 2017 American Society of Hematology (ASH) Annual Meeting.
“It is exciting to build upon our successful translational research and to expand the clinical research of PT-112 into treating patients with relapsed or refractory multiple myeloma,” said Robert Fallon, president and CEO of Phosplatin Therapeutics, in a press release.