US FDA Grants Orphan Drug Status To Sanofi’s GPRC5D-Targeting Monoclonal Antibody For Multiple Myeloma

The United States Food and Drug Administration (FDA) has granted Orphan Drug Designation to SAR446523, a monoclonal antibody developed by pharma major Sanofi, for the treatment of patients with relapsed or refractory multiple myeloma (MM), the French pharmaceutical company announced on Thursday.

The designation, intended to encourage the development of treatments for rare diseases, underscores the high unmet clinical need in this patient group and highlights the therapeutic potential of the GPRC5D-targeting candidate.

SAR446523 is an IgG1-based monoclonal antibody engineered to enhance antibody-dependent cellular cytotoxicity. It acts by targeting G protein-coupled receptor, class C, group 5, member D (GPRC5D), a cell surface antigen expressed in myeloma cells, said the Sanofi in the press release..

Multiple myeloma, the second most prevalent haematologic malignancy worldwide, is characterised by the proliferation of abnormal plasma cells, leading to complications such as renal dysfunction, anaemia, and skeletal fragility. Globally, over 1.8 lakh new cases are diagnosed annually. Despite advancements in treatment, MM remains incurable, with most patients eventually relapsing. The five-year survival rate in newly diagnosed cases remains approximately 62%.

The current treatment landscape offers several therapeutic modalities, including immunomodulatory agents, proteasome inhibitors, monoclonal antibodies, and autologous stem cell transplantation. However, outcomes remain suboptimal, particularly for patients ineligible for transplantation or those who progress after multiple lines of therapy.

“The Orphan Drug Designation is a significant milestone in our pursuit to deliver novel treatments to patients with relapsed or refractory multiple myeloma,” Dr. Alyssa Johnsen, Global Therapeutic Area Head for Immunology and Oncology Development at Sanofi said in a press release.

The safety, antitumour activity, pharmacokinetics, and pharmacodynamics of SAR446523 are currently being investigated in the TED18162 trial, a phase 1, first-in-human, open-label study (NCT06630806), focused on patients with relapsed or refractory MM. The drug has not yet received marketing approval from any regulatory agency.

In India, multiple myeloma accounts for approximately 1.19 per cent of all cancers. The crude incidence rate stands at 1.27 per 1,00,000 among men and 0.95 among women, with higher age-adjusted rates observed in individuals aged 60 years and above. The disease shows a mild male predominance.

The FDA’s Orphan Drug Designation is conferred on therapies targeting conditions that affect fewer than 200,000 people in the United States. The status offers development incentives, including tax credits, market exclusivity upon approval, and regulatory assistance.

While the designation marks a regulatory milestone, experts say that SAR446523 remains under clinical evaluation and should not be considered an established treatment at this stage.