FDA Approves Romiplostim sBLA for ITP

The US Food and Drug Administration (FDA) has approved the supplemental Biologics License Application (sBLA) for romiplostim (Nplate) as a treatment for adults with immune thrombocytopenia (ITP).

The indication expands romiplostim’s treatment for the rare autoimmune disease to include newly diagnosed and persistent adults ITP patients who have had an insufficient response to corticosteroids, immunoglobulins, or splenectomy.

Another sBLA for the Amgen therapy was approved last December, indicating it for pediatric ITP treatment.

The FDA granted the sBLA approval based on the results of an open-label, single-arm phase 2 trial assessing 75 adults with ITP diagnosed ≤ 6 months prior who had an insufficient response to initial treatment, including corticosteroids.

Median number of months with platelet response was 11, during the 12-month treatment period (95% CI, 10-11), with a median 2.1 weeks’ time to first platelet response (95% CI, 1.1-3.0). Another 70 (93%) patients achieved at least 1 platelet response during the 12-month period, and 24 (32%) achieved remission for at least 6 months.

Romiplostim’s safety profile was observed to be similar across patients, regardless of ITP duration. Common adverse reactions among treated patients included bronchitis, sinusistis, vomiting, arthralgia, myalgia, headache, dizziness, and diarrhea, among other conditions. Adverse reactions occurred in approximately 2% of adults with ITP, treated for up to 12 months.

David M. Reese, MD, executive vice president of Research and Development at Amgen, said these data are the first of their kind to examine the ITP outcome of treatment-free remission.

“Thirty-two percent of patients who received Nplate soon after an insufficient response to the first course of steroids maintained platelet response for at least six months without Nplate or any other ITP therapy," Reese said in a statement. "This approval will provide patients the opportunity to receive Nplate earlier in the course of their disease, potentially reducing their need for prolonged steroid use. We are excited to make Nplate available to more patients with this rare blood disorder."

Caroline Kruse, president and chief executive officer of the Platelet Disorder Support Association, echoed the need for treatment options that can deliver sustained ITP remission.

“The addition of this new data will help physicians and patients communicate and weigh the benefits and risks of treatment to find an appropriate treatment choice," Kruse said.