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FDA Approval of Caplacizumab for Acquired Thrombotic Thrombocytopenic Purpura
On February 6, 2019, in conjunction with plasma exchange and immunosuppressive treatment, approved caplacizumab-yhdp (CABLIVI, Ablynx NV) for adult patients with acquired thrombotic thrombocytopenic purpura (aTTP).
The approval was based on a multicenter randomized, double-blind, placebo-controlled trial (HERCULES) (NCT02553317) involving 145 caplacizumab-yhdp (n=72) or placebo (n=73) randomized patients. Plasma exchange and immunosuppressive therapy were given to patients in both classes. Patients obtained a single 11 mg intravenous injection of caplacizumab-yhdp bolus or placebo prior to the first plasma exchange study accompanied by a daily subcutaneous injection of caplacizumab-yhdp (11 mg) or placebo following completion of the plasma exchange, for a duration of daily plasma exchange, and for a period of 30 days afterwards.
If after the initial treatment course, signs of persistent underlying disease such as suppressed ADAMTS13 activity levels remained present, treatment was extended for 7-day intervals for a maximum of 28 days.
HERCULES Trial Results: Efficacy and Recurrence Rates
Caplacizumab-yhdp efficacy was determined on the basis of time-to-platelet count response (platelet count ~150,000/μL followed by daily plasma exchange cessation within 5 days). Compared to placebo, the time-to-platelet count response was faster among patients treated with caplacizumab-yhdp. Caplacizumab-yhdp therapy resulted in a lower number of patients during the treatment period with TTP-related deaths (0 vs. 3) and TTP recurrence (3 vs. 28). The proportion of patients with recurrence of TTP was lower in the caplacizumab-yhdp group (9/72 patients [13%]) compared to those receiving placebo (28/73 patients [38%]; p<0.001) over the total study duration (drug treatment period plus 28-day follow-up following discontinuation of drug treatment).
Recommended Dosage and Adverse Reactions
Epistaxis, fever, and gingival bleeding were the most common adverse reactions in at least 15 percent of patients receiving caplacizumab-yhdp.
The prescribed first dose of caplacizumab-yhdp is 11 mg bolus intravenous injection at least 15 minutes prior to plasma exchange, followed by 11 mg subcutaneous injection at the end of plasma exchange, 30 days after the last plasma exchange, on a daily basis. View the full prescription information for CABLIVI for additional dosing information.
Healthcare professionals should report all serious adverse events suspected to be associated with the use of any medicine and device to FDA’s MedWatch Reporting System or by calling 1-800-FDA-1088.
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About Susan Hau
Susan Hau is a distinguished researcher in the field of cancer cell therapy, with a particular focus on T cell-based approaches and cancer vaccines. Her work spans several innovative treatment modalities, including CAR T-cell therapy, TIL (Tumor-Infiltrating Lymphocyte) therapy, and NK (Natural Killer) cell therapy. Hau's expertise lies in cancer cell biolo…
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This article is for educational purposes only and should not replace medical advice, diagnosis, or treatment from a qualified oncology specialist. Every patient's case is different. Treatment decisions should always be made after a review of complete medical records by the treating medical team.
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