• Open Access

A Phase I, dose-finding and pharmacokinetic study of olaparib (AZD2281) in Japanese patients with advanced solid tumors

Authors


  • An abstract of preliminary results from this study was presented at ESMO 2010: Yamamoto N, Nokihara H, Yamada Y, Goto Y, Tanioka M, Shibata T, Yamada K, Asahina H, Tamura T. Encouraging data from a Phase I study of the first oral PARP inhibitor olaparib in Japanese patients with solid tumors. Ann Oncol 2010; 21 (Suppl 8): viii 176 (abst 537P).

  • ClinicalTrials.gov identifier NCT00572364.

To whom correspondence should be addressed.
E-mail: nbryamam@ncc.go.jp

Abstract

Olaparib (AZD2281) is an orally active Poly(ADP-ribose) polymerase (PARP) inhibitor with favorable antitumor activity in advanced ovarian and breast cancers with BRCA1/2 mutations in Western (USA and European) studies. This Phase I dose-finding study evaluated the tolerability, pharmacokinetics, PARP inhibitory activity, and antitumor activity of olaparib in Japanese patients with solid tumors. Olaparib was administered as a single-dose on day 1, followed by twice-daily dosing for 28 days from 48 h after a single dose. Doses were escalated from 100 mg b.i.d. in successive cohorts, up to a maximum of 400 mg b.i.d. The present study enrolled 12 patients (n = 3, 3, and 6 in 100, 200 and 400-mg b.i.d. levels, respectively). The most common adverse events were nausea, increased blood creatinine, decreased hematocrit, leukopenia and lymphopenia; dose-limiting toxicities were not observed up to and including the 400-mg b.i.d. dose level. Following twice-daily dosing, olaparib showed no marked increase in exposure at steady state over that expected from the single-dose pharmacokinetics. PARP-1 inhibition was observed from the 100-mg b.i.d. dose level in peripheral blood mononuclear cells from 6 h post-dose on day 1 during the multiple-dosing period. A patient with metastatic breast cancer (100 mg b.i.d.) had a partial response for 13 months and four patients (two each in the 200 and 400-mg b.i.d. levels) had stable disease >8 weeks. Olaparib was well tolerated up to the 400-mg b.i.d. dose in Japanese patients with solid tumors. Preliminary evidence of antitumor activity was observed. (Cancer Sci 2012; 103: 504–509)

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