tration (2.2)]. Patients should be observed closely for IRR reactions, especially during the first infusion.
One case of a serious, allergic/anaphylactic-like reaction has been observed in clinical trials of single-agent KADCYLA. Medications to treat such reactions, as well as emergency equipment, should be available for immediate use.
5.6 Thrombocytopenia
Thrombocytopenia, or decreased platelet count, was reported in clinical trials of KADCYLA (103 of 884 treated patients with ≥ Grade 3; 283 of 884 treated patients with any Grade). The majority of these patients had Grade 1 or 2 events (< LLN to ≥ 50,000/mm3) with the nadir occurring by day 8 and generally improving to Grade 0 or 1 (≥ 75,000 /mm3) by the next scheduled dose. In clinical trials of KADCYLA, the incidence and severity of thrombocytopenia were higher in Asian patients. Independent of race, the incidence of severe hemorrhagic events in patients treated with KADCYLA was low.
In the randomized trial (Study 1), the overall frequency of thrombocytopenia was 31.2% in the KADCYLA-treated group and 3.3% in the lapatinib plus capecitabine-treated group [see Adverse Reactions (6.1)]. The incidence of ≥ Grade 3 thrombocytopenia was 14.5% in the KADCYLA-treated group and 0.4% in the lapatinib plus capecitabine-treated group. In Asian patients, the incidence of ≥ Grade 3 thrombocytopenia was 45.1% in the KADCYLA-treated group and 1.3% in the lapatinib plus capecitabine-treated group.
Monitor platelet counts prior to initiation of KADCYLA and prior to each KADCYLA dose [see Dosage and Administration (2.2)]. KADCYLA has not been studied in patients with platelet counts <100,000/mm3 prior to initiation of treatment. In the event of decreased platelet count to Grade 3 or greater (< 50,000/mm3) do not administer KADCYLA until platelet counts recover to Grade 1 (≥ 75,000/mm3) [see Dosage and Administration (2.2)]. Patients with thrombocytopenia (< 100,000/mm3) and patients on anti-coagulant treatment should be closely monitored during treatment with KADCYLA.
.7 Neurotoxicity
Peripheral neuropathy, mainly as Grade 1 and predominantly sensory, was reported in clinical trials of KADCYLA (14 of 884 treated patients with ≥ Grade 3; 196 of 884 treated patients with any Grade). In the randomized trial (Study 1), the overall frequency of peripheral neuropathy was 21.2% in the KADCYLA-treated group and 13.5% in the lapatinib plus capecitabine-treated group [see Adverse Reactions (6.1)]. The incidence of ≥ Grade 3 peripheral neuropathy was 2.2% in the KADCYLA-treated group and 0.2% in the lapatinib plus capecitabine-treated group.
KADCYLA should be temporarily discontinued in patients experiencing Grade 3 or 4 peripheral neuropathy until resolution to ≤ Grade 2. Patients should be clinically monitored on an ongoing basis for signs or symptoms of neurotoxicity [see Nonclinical Toxicology (13.2)].
5.8 HER2 Testing
Detection of HER2 protein overexpression or gene amplification is necessary for selection of patients appropriate for KADCYLA therapy because these are the only patients studied for whom benefit has been shown [see Indications and Usage (1), Clinical Studies (14.1)]. In the randomized study (Study 1), patients with breast cancer were required to have evidence of HER2 overexpression defined as 3+ IHC by Dako Herceptest™ or evidence of overexpression defined as FISH a |
