- The FDA has approved a subcutaneous formulation of trastuzumab that strikingly reduces administration time in human epidermal growth factor receptor 2 (HER2)-positive breast cancer.
- Subcutaneous trastuzumab consists of trastuzumab plus hyaluronidase, an enzyme used to hasten absorption. Administration takes 2-5 minutes, according to an FDA news release, instead of 30-90 minutes with intravenous (IV) trastuzumab, according to a Genentech news release.
Why this matters
- Subcutaneous trastuzumab is a new, more efficient treatment option.
- Prescribing information is here.
- Subcutaneous trastuzumab carries the same indications as the IV formulation for adjuvant treatment of HER2+ breast cancer and metastatic breast cancer, but is not indicated for metastatic gastric cancer.
- The recommended dose is 600 mg trastuzumab and 10,000 units hyaluronidase once every 3 weeks.
- Approval of subcutaneous trastuzumab was based on 2 trials, HannaH and SafeHER.
- HannaH (N=596) showed noninferior pharmacokinetics and pathologic complete response with subcutaneous vs IV trastuzumab.
- SafeHER (N=1864) was a nonrandomized trial assessing safety of a 600-mg fixed dose of subcutaneous trastuzumab. The most frequent adverse events (in ≥10% of patients) included fatigue, arthralgia, diarrhea, and injection site reaction, according to the FDA news release.