Osimertinib is a tyrosine kinase inhibitor used to treat patients with non-small cell lung cancer (NSCLC) whose tumors have been identified—via an FDA-approved test—as harboring specific epidermal growth factor receptor (EGFR) gene abnormalities.
Indications for Osimertinib
1. Adjuvant Therapy in Adults (Post-Surgical Prevention of Recurrence)
(1) Tumors harboring EGFR exon 19 deletions or exon 21 L858R mutations.
(2) Tumors that have been surgically resected.
(3) Cancer that is locally advanced and unresectable (Stage III), and has not progressed during or after concurrent or sequential platinum-based chemoradiation therapy.
2. First-Line Monotherapy (Metastatic Cancer)
Indicated for adult patients whose tumors harbor EGFR exon 19 deletions or exon 21 L858R mutations, and whose cancer has metastasized (spread to other parts of the body).
3. First-Line Combination Therapy (Locally Advanced or Metastatic Cancer)
Used in combination with pemetrexed and platinum-based chemotherapy to treat adult patients whose tumors harbor EGFR exon 19 deletions or exon 21 L858R mutations, and whose cancer is locally advanced (spread to adjacent tissues) or metastatic.
4. Treatment of Patients with EGFR T790M Mutations
Used to treat adult patients with NSCLC whose tumors harbor the EGFR T790M mutation, whose cancer has metastasized, and whose disease has progressed on or after prior therapy with an EGFR tyrosine kinase inhibitor (TKI).
Osimertinib Safety Warnings
1. Fetal Risk: Tagrisso may cause harm to a developing fetus.
2. Females of Reproductive Potential: Effective contraception must be used during treatment and for 6 weeks following the last dose.
3. Males with Female Partners of Reproductive Potential: Effective contraception must be used during treatment and for 4 months following the last dose.
Common Side Effects of Osimertinib
1. As Monotherapy
Leukopenia, lymphopenia, neutropenia (low white blood cell count), thrombocytopenia (low platelet count), anemia (low red blood cell count), diarrhea, rash, musculoskeletal pain, nail toxicity, dry skin, stomatitis (mouth ulcers), fatigue.
2. In Combination with Chemotherapy (Used in combination with Pemetrexed and Platinum-based agents)
Leukopenia, lymphopenia, neutropenia, thrombocytopenia, rash, diarrhea, stomatitis, nail toxicity, dry skin, elevated blood creatinine.
