Trial Information

A Phase Ⅱ Single-arm Clinical Trial to Investigate the Efficacy and Safety of Vinorelbine-ifosfamide Regimen as Third-line Treatment in Refractory or Recurrent Extensive Small Cell Lung Cancer Patients

Small cell lung cancer (SCLC) is a highly aggressive disease characterized by its rapid
doubling time, high growth fraction, early development of disseminated disease, and dramatic
response to first-line chemotherapy and radiation. Small cell lung cancer accounts for
approximately 20%-25% lung cancer patients. SCLC patients are categorized as limited
disease, defined as disease that is confined to the ipsilateral hemithorax that can be
encompassed within a tolerable radiation port, or extensive disease (ED), defined as the
presence of overt metastatic disease determined by imaging or physical examination. Two
third of patients are diagnosed with ED at presentation. Despite the development of novel
cytotoxic drugs, the therapeutic approach to SCLC has been stagnant for more than twenty
years. Standard treatment for ED-SCLC remains EP or CE, a regimen that yield a median
survival of approximately 9 months and a 5-year survival of less than 1%.

Most patients are destined to relapse, and the prognosis for this group of patients who
relapse is poor. Patients who relapse < 3 months after first-line therapy are commonly
called refractory, and patients who relapse 3 months after therapy are labeled as sensitive.
In a randomized multicenter study, von Pawel et al compared cyclophosphamide, adriamycin,
and vincristine (CAV) with topotecan as a single agent in patients who had relapse at least
60 days (2 months) after initial therapy. The response rates were 24.3% in patients treated
with topotecan and 18.3% in patients treated with CAV (P=0.285). Median times to progression
were 13.3 weeks for the topotecan arm and 12.3 weeks for the CAV arm. Median survival times
were 25 weeks for topotecan and 24.7 weeks for CAV. The proportion of patients with symptom
improvement was greater in the topotecan arm than in the CAV arm. The authors concluded
that topotecan was at least as effective as CAV in the treatment of patients with recurrent
SCLC. So in some guidelines for SCLC, topotecan is recommended as the standard second-line
treatment in patients who relapse less than 3 months. As for patients who relapse more than
six months after the end of initial treatment, EP or CE regimen is recommended to be used
again.