- Clinical Trials
A phase I/II clinical trial evaluated GPX-001 in combination with Tarceva® (erlotinib) in stage IIIB/IV lung cancer patients without an activating EGFR mutation and in patients with an activating EGFR mutation whose cancer has progressed on erlotinib therapy was conducted at MD Anderson Cancer Center. Patients without the EGFR mutation represent the vast majority of lung cancer patients. However, such patients generally are not candidates for Tarceva therapy.
Osimertinib is now considered a new standard of care in the United States for NSCLC patients with an EGFR mutation. Given this and our receipt of the FDA’s Fast Track Designation for use of GPX-001 combined with osimertinib in patients whose tumors progress on osimertinib, we have decided to prioritize this drug combination and patient population. Therefore, we plan to initiate a Phase I/II clinical trial of GPX-001 combined with osimertinib, and do not intend to reopen enrollment in the current Phase I/II trial using the combination of GPX-001 and erlotinib at this time.
In the Phase II trial combining GPX-001 with erlotinib, subjects received GPX-001 in combination with erlotinib every 21 days until the occurrence of progressive disease (PD), unacceptable toxicity, withdrawal of consent, or study treatment discontinuation for other reasons, whichever occurred first. We believe that the results from the Phase II trial are encouraging. Out of 10 patients, 9 had received 2 or more cycles and were therefore evaluable for response. Four patients had tumor regression. The median duration of response is 3 months. The disease control rate (CR+PR+SD > 8weeks) was 78%, which substantially exceeds the 7% response rate (with no CRs) and 58% disease control rate reported for the LUX-Lung 1 trial, a clinical trial of afatinib (Gilotrif®) in a comparable group of patients.
One patient in the Phase II combination trial had a Complete Response, or CR, under the Response Evaluation Criteria in Solid Tumors, or RECIST. This patient, a 58 year old female, upon enrollment in the study had metastatic NSCLC status following 6 cycles of pemetrexed and carboplatin and 2 cycles of maintenance pemetrexed with cancer progression. The patient’s tumor has EGFR exon 18 and 20 missense mutations, which are not sensitive to erlotinib. This patient had disappearance of both the lung primary tumor and the lung, liver, and lymph node metastases.
Tarceva® is a registered trademark of Astellas and the Roche Group of companies.
Gilotrif® is a registered trademark of Boehringer Ingelheim.