FDA approves sBLA for Nplate in immune thrombocytopenia.- Amgen

Amgen announced that the FDA has approved Amgen's Supplemental Biologics License Application (sBLA) for Nplate (romiplostim) to include new data in its U.S. prescribing information showing sustained platelet responses in adults with immune thrombocytopenia (ITP), a rare, serious autoimmune disease characterized by low platelet counts. The updated indication expands treatment with Nplate to newly diagnosed and persistent adult ITP patients who have had an insufficient response to corticosteroids, immunoglobulins or splenectomy. In December of last year, the FDA approved another sBLA for Nplate in the treatment of pediatric patients with ITP.

The sBLA was based on an open-label, single-arm Phase II trial of adults with ITP diagnosed ? 6 months prior who had an insufficient response to first-line treatment, including corticosteroids (N=75). The median time from ITP diagnosis to study enrollment was 2.2 months. On the primary endpoint, the median number of months with platelet response (at least 50 x 109/L) was 11 months during the 12-month treatment period (95% CI: 10, 11), with a median time to first platelet response of 2.1 weeks (95% CI: 1.1, 3.0). Additionally, 93% (70) of patients achieved one or more platelet responses during the 12-month treatment period. On the secondary endpoint, 32% (24) of patients achieved remission for at least six months, defined by maintaining a platelet count at least 50 x 109/L in the absence of Nplate and any medication for ITP (concomitant or rescue).

The safety profile of Nplate was similar across patients, regardless of ITP duration. The following adverse reactions (at least 5% incidence and at least 5% more frequent with Nplate compared with placebo or standard of care) occurred in Nplate patients with ITP duration up to 12 months: bronchitis, sinusitis, vomiting, arthralgia, myalgia, headache, dizziness, diarrhea, upper respiratory tract infection, cough, nausea and oropharyngeal pain. The adverse reaction of thrombocytosis occurred with an incidence of 2% in adults with ITP duration up to 12 months.