n the sensitivity and the specificity of the assay.
Additionally, the observed incidence of antibody (including neutralizing antibody) positivity in an assaymay be influenced by several factors including assay methodology, sample handling, timing of samplecollection, concomitant medications, and underlying disease. For these reasons, comparison of theincidence of antibodies in the studies described below with the incidence of antibodies in other studies or toother trastuzumab products may be misleading.
Among 903 women with metastatic breast cancer, human anti-human antibody (HAHA) to trastuzumab wasdetected in one patient using an enzyme-linked immunosorbent assay (ELISA). This patient did not experiencean allergic reaction. Samples for assessment of HAHA were not collected in studies of adjuvant breast cancer.
6.3 Post-Marketing Experience
The following adverse reactions have been identified during post-approval use of trastuzumab. Because thesereactions are reported voluntarily from a population of uncertain size, it is not always possible to reliablyestimate their frequency or establish a causal relationship to drug exposure.
Oligohydramnios or oligohydramnios sequence, including pulmonary hypoplasia, skeletal abnormalities,and neonatal death [see Warnings and Precautions (5.3)]
Glomerulopathy [see Adverse Reactions (6.1)]
Immune thrombocytopenia
Tumor lysis syndrome (TLS): Cases of possible TLS have been reported in patients treated withtrastuzumab. Patients with significant tumor burden (e.g. bulky metastases) may be at a higher risk.
Patients could present with hyperuricemia, hyperphosphatemia, and acute renal failure which mayrepresent possible TLS. Providers should consider additional monitoring and/or treatment as clinicallyindicated.
7 DRUG INTERACTIONS
Patients who receive anthracycline after stopping trastuzumab products may be at increased risk of cardiacdysfunction because of trastuzumab's long washout period based on population PK analysis [see ClinicalPharmacology (12.3)]. If possible, physicians should avoid anthracycline-based therapy for up to 7 months
after stopping trastuzumab products. If anthracyclines are used, the patient's cardiac function should bemonitored carefully.
8 USE IN SPECIFIC POPULATIONS
8.1 Pregnancy
Risk Summary
Trastuzumab products can cause fetal harm when administered to a pregnant woman. In post-marketingreports, use of trastuzumab during pregnancy resulted in cases of oligohydramnios and ofoligohydramnios sequence, manifesting as pulmonary hypoplasia, skeletal abnormalities, and neonataldeath [see Data]. Apprise the patient of the potential risks to a fetus. There are clinical considerations iftrastuzumab products are used in a pregnant woman or if a patient becomes pregnant within 7 monthsfollowing the last dose of a trastuzumab product [see Clinical Considerations].
The estimated background risk of major birth defects and miscarriage for the indicated population isunknown. In the U.S. general population, the estimated background risk of major birth defects andmiscarriage in clinically recognized pregnancies is 2% to 4% and 15% to 20%, respectively.
Clinical Considerations
Fetal/Neonatal Adverse Reactions
Monitor women who received KANJINTI during pregnancy or within 7 months prior to conception foroligohydramnios. If oligohydramnios occurs, perform fetal testing that is |
