Final report of post-marketing survey of panitumumab in Japanese patients with unresectable advanced or recurrent colorectal cancer.

Abstract

525 Background: Panitumumab (P-mab) was approved in Japan in Apr. 2010 for the treatment of unresectable, advanced or recurrent colorectal cancer with wild-type KRAS, both in monotherapy and in combination with chemotherapy for all lines of treatment. All-case surveillance of P-mab was conducted to assess safety and efficacy in practical use since clinical data on Japanese patients were limited. Methods: All patients were registered before starting P-mab containing therapy by central registration method since the launch of P-mab in Japan. Patients were examined for eligibility requirements such as KRAS genotype (wild), ECOG PS (0-2) and interstitial pneumonitis (-). Skin disorder, infusion reaction(IR), electrolyte abnormality, cardiac disorder, interstitial lung disease (ILD) were surveyed with special interest. Results: 3,091 patients were registered from Jun. 2010 to Nov. 2010 and interim analysis were made with 3,005 patients at the point of Oct. 2011. The interim analysis; male: 63.6%, mean age: 65 y.o., KRAS wild/ mutant/ not determinable: 97.3%/0.1%/2.6%. Proportion of first line/second line/third line or later treatment: 10.4%/18.0%/71.6%, PS 0-1/2/3/4: 91.3%/7.9%/0.7%/0.1%. P-mab monotherapy/combination: 41.0%/58.8%. Combination regimens: FOLFOX/FOLFIRI/other regimens: 18.7%/33.4%/15.2%. Overall incidence of ADRs:83.7 %, and that of Grade 3 or higher ADRs:24.7 %. Incidence of ADRs of special interest: skin disorder 77.8%, IR 1.5%, electrolyte abnormality18.3%, cardiac disorder 0.2%, ILD 1.3% (0.6% fatal). Incidences of ILD were similar in monotherapy and in combination. The median survival time of patients with P-mab monotherapy as third line or later treatment was 10.3 months, 95%CI (9.0-11.3). Result of final analysis with 3086 patients(99.8% of registerd patients) at the point of Jun. 2012 is to be presented in this meeting. Conclusions: The safety profile of P-mab in the post-marketing use was similar to that previously reported in the clinical trials. The risk/benefit balance for use of P-mab in patients with unresectable colorectal cancer remains favorable.