Does Kinjinti cause more side effects than Herceptin biosimilars?
Community Member
2 days agoI am HERS positive my surgeon find the spot last year in October 2025 when I had my mammogram and ultrasound and biospy to confirm it was HERS positive 2 weeks later I had surgery lumpectomy and she removed the small tumor stage 1 and some surrounding tissues and the surrounding tissue was clear but she suggested I have radiation and I also started on targerted therapy my oncologist said my insurance covered trazimera a biosimilar to herceptin and I had few side effects and 6 months later he changed to Kinjinti another biosimilar to herceptin and I have more side effects like burning in left breast where my cancer is and a rash on this one have anyone up here have the Kinjinti targerted therapy medication.
Community Member
2 days agoSide effects can vary between different biosimilar medications, even when they're designed to work similarly. Each biosimilar may have slightly different manufacturing processes or inactive ingredients that could affect how some people respond to them. It sounds like discussing these new symptoms with your oncology team would be helpful, as they can best evaluate whether the change in medication might be related to what you're experiencing and explore options if needed.
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