Opna Bio's OPN-6602 Granted Orphan Drug Status for Multiple Myeloma

Opna Bio, a clinical-stage biopharmaceutical company based in South San Francisco, California, has announced a significant milestone in its quest to develop innovative cancer treatments. The U.S. Food and Drug Administration (FDA) has granted orphan drug designation (ODD) to Opna Bio’s leading drug candidate, OPN-6602, for the treatment of multiple myeloma (MM). OPN-6602 is an oral small molecule that inhibits the E1A binding protein (EP300) and CREB-binding protein (CBP). The drug is currently being tested in a Phase 1 clinical trial involving patients with relapsed or refractory multiple myeloma.

Multiple myeloma is a rare and aggressive form of cancer that affects plasma cells in the bone marrow. This condition can lead to severe complications, including bone damage, kidney failure, and weakened immune function. The disease primarily affects older adults, and treatment options are limited, especially for those who relapse or whose disease is resistant to standard therapies.

Gideon Bollag, Ph.D., the chief scientific officer of Opna Bio, expressed satisfaction at receiving the FDA's orphan drug designation. He emphasized that this recognition underscores the potential of OPN-6602 as a therapeutic option for patients with multiple myeloma who have few alternatives once their disease returns.

The FDA’s orphan drug designation is designed to support the development of treatments for rare diseases, which are defined as affecting fewer than 200,000 people in the United States. This status offers several advantages to the drug developer, including tax credits for clinical trial expenses, exemption from certain FDA fees, and eligibility for seven years of market exclusivity once the drug is approved.

In December 2024, Opna Bio presented promising data at the American Society of Hematology (ASH) meeting. The findings demonstrated that OPN-6602 effectively suppresses tumor growth in human-derived multiple myeloma models while downregulating critical genes that drive the disease. The drug showed synergistic effects when used in combination with dexamethasone, pomalidomide, and mezigdomide. OPN-6602's unique pharmacokinetic properties allow for continuous daily dosing, which may lead to reduced toxicity and enhanced therapeutic efficacy.

The ongoing Phase 1 clinical study (NCT06433947) involving patients with relapsed or refractory multiple myeloma is being conducted at various locations across the United States. Opna Bio anticipates completing the dose-escalation phase of this trial by 2026. The company also plans to explore further development of OPN-6602 in combination with existing standard-of-care treatments for multiple myeloma.

Opna Bio is committed to discovering and developing novel cancer therapeutics. Its comprehensive portfolio targets multiple cancer drivers, including a novel discovery program focused on the fragile-X multifunctional RNA-binding protein (FMRP) and a diverse pipeline of promising oncology assets. The Opna Bio team boasts a proven track record of scientific expertise and commercial success, having successfully brought several FDA-approved medications to market. The company’s leading clinical compounds include OPN-2853, a potentially best-in-class BET bromodomain inhibitor being evaluated in myelofibrosis patients alongside ruxolitinib, and OPN-6602, a dual EP300/CBP inhibitor currently being studied in its first human clinical trial for multiple myeloma.