How effective is gefitinib at treating advanced non-small-cell lung cancer?

This study summarized the effectiveness of gefitinib for treating advanced non-small-cell lung cancer. The authors concluded that gefitinib may be beneficial for prolonging time until progression and quality of life, particularly for patients with the specific genetic mutation EGFR.

Cancers can be caused by specific genetic mutations (changes), including a mutation called EGFR. Cancer treatments that target this mutation are called EGFR-TKIs. One example of an EGFR-TKI is gefitinib (Iressa). Targeted therapies have increased survival rates for many types of cancers. The exact effect of gefitinib at treating advanced non-small-cell lung cancer (NSCLC) remains unknown.

This study examined the effectiveness and safety of gefitinib for treating advanced NSCLC. The authors combined data from 35 trials, with a total of 12,089 patients. They recorded overall survival (OS, time from beginning trial until death), progression free survival (PFS, time from beginning trial until disease progression), side effects, tumor response and quality of life.

Overall, gefitinib did not result in improved OS compared to chemotherapy or placebo (no therapy). As a second-line treatment, it resulted in an 18% longer time to treatment failure compared to placebo. As maintenance therapy (treatment following first option treatment to improve the outcome), treatment with gefitinib improved PFS by 30%.

The authors also specifically looked at the effect of gefitinib in Asian populations. As a first option treatment, PFS was 35% longer compared to chemotherapy for this population of patients. Furthermore, gefitinib in combination with chemotherapy was 31% better than either gefitinib or chemotherapy alone. As a second-line treatment, gefitinib resulted in 31% prolonged PFS compared to placebo. A combination of gefitinib and chemotherapy in a second-line setting was 35% better than gefitinib alone. As maintenance therapy, gefitinib improved PFS by 58% compared to placebo.

For patients with the EGFR mutation, gefitinib as first option treatment resulted in a 53% improvement in PFS compared to chemotherapy and a 76% improvement as a second-line treatment. As maintenance therapy, compared to placebo, gefitinib improved OS by 61% and PFS by 83%.

Side effects from treatment with gefitinib included rash, diarrhea and liver damage. Compared to chemotherapy, patients treated with gefitinib had a better quality of life with less toxic side effects.

The authors concluded that gefitinib was beneficial for improving PFS and quality of life compared to chemotherapy. This was specific to patients with EGFR mutations. They stated that combining gefitinib with chemotherapy may be beneficial, but further study is needed.