WARNING: THROMBOTIC EVENTS AND ACUTE AND RECURRENT GALLBLADDER DISEASE
THROMBOTIC EVENTS
Serious thrombotic events have occurred in Qfitlia-treated patients with risk factors for thromboembolism including persistent antithrombin (AT) activity less than 15%, use of Qfitlia 80 mg once monthly, presence of indwelling venous catheters, and in the post-operative setting when Bleed Management Guidelines were not followed.
Monitor AT activity using an FDA-cleared test and target AT activity 15-35% to reduce the risk of thrombosis. Monitor patients for signs and symptoms of thrombotic events. Interrupt Qfitlia in patients with a thrombotic event and manage as clinically indicated.
ACUTE AND RECURRENT GALLBLADDER DISEASE
Acute and recurrent gallbladder disease, including cholelithiasis and cholecystitis have occurred in Qfitlia-treated patients, some of whom required cholecystectomy or had complications (e.g., pancreatitis) related to gallbladder disease. Monitor patients for signs and symptoms of acute and recurrent gallbladder disease.
Consider interruption or discontinuation of Qfitlia if gallbladder disease occurs. Consider alternative treatment for hemophilia in patients with a history of symptomatic gallbladder disease.
WARNINGS AND PRECAUTIONS
Thrombotic Events:
- Serious thrombotic events have been reported in Qfitlia-treated patients. Thrombotic events were reported in 2.6% of patients receiving the 80 mg once monthly dose, including a fatal event of cerebral venous sinus thrombosis. The 80 mg once monthly dose is not approved or recommended for use. Thrombotic events were reported in 1.4% of patients receiving Qfitlia prophylaxis using the AT-based dose regimen (AT-DR) that targeted AT activity 15-35%.
- The risk of thrombosis is greater in patients with certain risk factors (see Boxed WARNING). Treatment of breakthrough bleeding episodes with clotting factor concentrate (CFC) or bypassing agent (BPA) at a dose greater or more frequent than recommended may also increase thrombotic risk.
Acute and Recurrent Gallbladder Disease:
- Treatment with Qfitlia is associated with an increased occurrence of acute and recurrent gallbladder disease, including cholelithiasis and cholecystitis (see Boxed WARNING). In the 270 patients in the clinical studies who received Qfitlia at a fixed dose of 80 mg once monthly, 17% experienced gallbladder events and 4% underwent cholecystectomy. In 286 patients who received the AT-DR, 3.8% experienced gallbladder events and 0.3% underwent cholecystectomy.
Hepatotoxicity:
- In the two randomized studies testing Qfitlia 80 mg once monthly, alanine transaminase (ALT) and aspartate transaminase (AST) elevations above 3 times the upper limit of normal (ULN) occurred in 32% of patients with hemophilia with inhibitors and 18% of patients with hemophilia without inhibitors. There was one case of moderate hepatic injury attributable to Qfitlia use. On the AT-DR, 3.4% of patients treated with Qfitlia had at least one ALT value >3x ULN.
- Avoid use of Qfitlia in patients with hepatic impairment (Child-Pugh Class A, B, and C).
- Obtain baseline liver tests, including AST, ALT, and total bilirubin, prior to initiating Qfitlia, monthly for at least the first 6 months of Qfitlia use, monthly for at least 6 months after a dose increase, and periodically thereafter as clinically indicated.
- If new or worsening liver test abnormalities occur, initiate medical management as appropriate and monitor until they return to baseline. If ALT or AST elevations >5x ULN occur, interrupt Qfitlia treatment. If Qfitlia is restarted and ALT or AST elevations >5x ULN reoccur or the patient experiences jaundice due to hepatotoxicity with other causes of liver test elevation ruled out, permanently discontinue Qfitlia.
DRUG INTERACTIONS
Hypercoagulability with Concomitant Use of CFC or BPA:
- Qfitlia prophylaxis leads to increased thrombin generation with additive increase in peak thrombin when used concomitantly with CFC or BPA.
ADVERSE REACTIONS
Common adverse reactions (incidence ≥10%) are viral infection, nasopharyngitis, and bacterial infection.
