OncoTherapy Science, Inc.
January 18, 2017

Poster presentation at 2017 Gastrointestinal Cancers Symposium (ASCO GI)
on Phase 1 Clinical Study of OTS103/104 (OCV-C02) for colorectal cancer
The Phase 1 Clinical Study of OTS103/104 (OCV-C02), a mixture of two peptide vaccines derived
from two oncoproteins frequently transactivated in various types of cancer including colorectal
cancer, which OncoTherapy Science, Inc. (President & CEO: Masaharu Mori) out-licensed toOtsuka Pharmaceutical Co., Ltd. (Head office: Chiyoda-ku, Tokyo, President and CEO: Tatsuo
Higuchi; hereinafter, “Otsuka”) has been conducted by Otsuka. The poster describing the resultsof this trial is going to be presented and the abstract has been published as below.
Otsuka has completed this trial by announcing the abstract of this poster presentation.

【Abstract】
Phase 1 trial of OCV-C02, a peptide vaccine for metastatic colorectal cancer patients refractory
to all standard chemotherapies.
Background: OCV-C02 is a peptide vaccine consisting of 2 peptide epitopes derived from ring
finger protein 43 and translocase of outer mitochondrial membrane 34. In colorectal cancer(CRC), they are upregulated in approximately 80% of tumor tissues. This study was conducted
to assess safety, preliminary efficacy and immunological responses to OCV-C02.
Methods: Key eligibility criteria for this open label, sequential cohort, dose escalation study werepatients (pts) with unresectable metastatic CRC (mCRC) refractory to all standard
chemotherapies and HLA-A*24:02. Pts in cohorts 1 to 4 received OCV-C02 0.3, 1, 3 and 6 mg/bodyrespectively, subcutaneously, on days 1, 8, 15 and 22 of the 28-day treatment cycle. Cycle wasrepeated in pts without progressive disease, until occurrence of unacceptable toxicity or diseaseprogression. Primary endpoint was dose limiting toxicity (DLT) that was defined as treatmentrelated ≥grade 3 or 4 hematological or ≥grade 3 non-hematological adverse events (AEs) observed
from days 1 to 29 of Cycle 1. Secondary endpoints were treatment emergent AEs (TEAEs),
efficacy and immunological responses. Efficacy was evaluated by overall response rate, disease
control rate (DCR), time to treatment failure (TTF) and overall survival (OS). Immunologicalresponses were evaluated by cytotoxic T lymphocytes (CTL) and delayed-type hypersensitivity(DTH).
Results: A total of 24 pts were treated. No DLT occurred in cycle 1 and no major safety issues
throughout the trial. All pts had ≥1 TEAE. Frequently reported TEAEs included injection site

reaction (25%), vomiting (25%), decreased appetite (20.8%) and pyrexia (16.7%). More than 50%
of TEAEs were of grade 1 or 2 in severity. None achieved complete or partial response. Six pts
had stable disease and DCR were 16.7%, 50% and 33.3% for cohorts 2, 3 and 4, respectively. TTF
was 1.8, 0.9, 2.3 and 1.6 months and OS was 7.9, 11.6, 8.4 and 7.4 months for cohorts 1, 2, 3 and4, respectively. CTL and DTH responses following vaccination were observed across the 4 cohorts.
Conclusions: OCV-C02 at 0.3 to 6 mg/body exhibited a safe and well tolerated profile, and showed
immunological responses in mCRC pts refractory to all standard chemotherapies.
(URL: http://meetinglibrary.asco.org/content/174849-195 )