Important Safety Information

Boxed WARNING: THROMBOTIC MICROANGIOPATHY and THROMBOEMBOLISM

Cases of thrombotic microangiopathy and thrombotic events were reported when on average a cumulative amount of > 100 U/kg/24 hours of activated prothrombin complex concentrate (aPCC) was administered for 24 hours or more to patients receiving HEMLIBRA prophylaxis. Monitor for the development of thrombotic microangiopathy and thrombotic events if aPCC is administered. Discontinue aPCC and suspend dosing of HEMLIBRA if symptoms occur.

Warnings and Precautions

Thrombotic Microangiopathy (TMA) Associated with HEMLIBRA and aPCC

Cases of thrombotic microangiopathy (TMA) were reported from clinical trials when on average a cumulative amount of >100 U/kg/24 hours of activated prothrombin complex concentrate (aPCC) was administered for 24 hours or more to patients receiving HEMLIBRA prophylaxis. In clinical trials, thrombotic microangiopathy was reported in 1.6% of patients (3/189) and in 8.3% of patients (3/36) who received at least one dose of aPCC. Patients presented with thrombocytopenia, microangiopathic hemolytic anemia, and acute kidney injury, without severe deficiencies in ADAMTS13 activity.

Evidence of improvement was seen within one week following discontinuation of aPCC. One patient resumed HEMLIBRA following resolution of TMA.

Consider the benefits and risks if aPCC must be used in a patient receiving HEMLIBRA prophylaxis. Monitor for the development of TMA when administering aPCC. Immediately discontinue aPCC and interrupt HEMLIBRA prophylaxis if clinical symptoms and/or laboratory findings consistent with TMA occur, and manage as clinically indicated. Consider the benefits and risks of resuming HEMLIBRA prophylaxis following complete resolution of TMA on a case-by-case basis.

Thromboembolism Associated with HEMLIBRA and aPCC

Thrombotic events were reported from clinical trials when on average a cumulative amount of >100 U/kg/24 hours of aPCC was administered for 24 hours or more to patients receiving HEMLIBRA prophylaxis. In clinical trials, thrombotic events were reported in 1.1% of patients (2/189) and in 5.6% of patients (2/36) who received at least one dose of aPCC.

No thrombotic event required anticoagulation therapy. Evidence of improvement or resolution was seen within one month following discontinuation of aPCC. One patient resumed HEMLIBRA following resolution of thrombotic event.

Consider the benefits and risks if aPCC must be used in a patient receiving HEMLIBRA prophylaxis. Monitor for the development of thromboembolism when administering aPCC. Immediately discontinue aPCC and interrupt HEMLIBRA prophylaxis if clinical symptoms, imaging, or laboratory findings consistent with thromboembolism occur, and manage as clinically indicated.Consider the benefits and risks of resuming HEMLIBRA prophylaxis following complete resolution of thrombotic events on a case-by-case basis.

Laboratory Coagulation Test Interference

HEMLIBRA affects intrinsic pathway clotting-based laboratory tests, including activated clotting time (ACT), activated partial thromboplastin time (aPTT), and all assays based on aPTT, such as one-stage factor VIII (FVIII) activity. Therefore, intrinsic pathway clotting-based laboratory test results in patients treated with HEMLIBRA should not be used to monitor HEMLIBRA activity, determine dosing for factor replacement or anti-coagulation, or measure FVIII inhibitor titers.

Results affected by HEMLIBRA: aPTT; Bethesda assays (clotting-based) for FVIII inhibitor titers; one-stage, aPTT-based, single-factor assays; aPTT-based Activated Protein C Resistance (APC-R); ACT.

Results unaffected by HEMLIBRA: Bethesda assays (bovine chromogenic) for FVIII inhibitor titers; thrombin time (TT); one-stage, prothrobin time (PT)-based, single-factor assays; chromogenic-based single-factor assays other than FVIII (see Drug Interactions for FVIII chromogenic activity assay considerations); immuno-based assays (ie, ELISA, turbidimetric methods); genetic tests of coagulation factors (e.g., Factor V Leiden, Prothrombin 20210).

Most Common Adverse Reactions

The most frequently reported adverse reactions observed in ≥ 10% of subjects treated with at least one dose of HEMLIBRA were injection site reactions, headache, and arthralgia.

Adverse Reactions

Characterization of aPCC Treatment in Pooled Clinical Trials

There were 125 instances of aPCC treatment in 36 patients, of which 13 instances (10.4%) consisted of on average a cumulative amount of >100 U/kg/24 hours of aPCC for 24 hours or more; two of the 13 were associated with thrombotic events and three of the 13 were associated with TMA. No TMA or thrombotic events were associated with the remaining instances of aPCC treatment.

Injection Site Reactions

In total, 35 patients (19%) reported injection site reactions (ISRs). All ISRs observed in HEMLIBRA clinical trials were reported as mild to moderate intensity and 88% resolved without treatment. The commonly reported ISR symptoms were injection site erythema (7.4%), injection site pruritus (5.3%), and injection site pain (5.3%).

Drug Interactions

Clinical experience suggests that a drug interaction exists with HEMLIBRA and aPCC. There is a possibility for hypercoagulability with activated recombinant factor VII (rFVIIa) or FVIII with HEMLIBRA based on preclinical experiments.

You may report side effects to the FDA at (800) FDA-1088 or www.fda.gov/medwatch. You may also report side effects to Genentech at (888) 835-2555.

Please see the HEMLIBRA full Prescribing Information for additional Important Safety Information, including Boxed WARNING.