A late phase II study of LY188011 (gemcitabine hydrochloride), a new nucleoside derivative, in patients with non-small-cell lung cancer (NSCLC) was conducted at 24 Japanese institutions shown in Table 1 with a total of 69 patients enrolled. Of these, 67 were eligible and 64 completed at least one course of LY188011 therapy. The response rates (partial response only) in these populations were 20.9% (14/ 67) and 21.9% (14/64), respectively. Serious adverse reactions were septic shock and interstitial pneumonia in one patient each. Grade 3 or 4 adverse reactions included neutropenia (22.7%), decreased hemoglobin (13.4%), leukopenia (10.4%), anorexia (10.4%), malaise (7.5%), and nausea/vomiting (6.0%). Based on these results, it may be concluded that LY188011 has a high efficacy and benefit for the treatment of NSCLC.