Highlights from ASCO

The 45th Annual Meeting of the American Society of Clinical Oncology (ASCO) was held from 29th May to 2nd June, in Orlando, FL. Whilst a previous editorial published in Cancer Drug News (see Issue No. 364 - "Looking ahead to ASCO") noted that the 4,000 study abstracts for this year's meeting had drawn a mainly disappointing response, there were numerous encouraging results reported. Of particular note were positive Phase III data with Roche's Herceptin (trastuzumab) in aggressive gastric cancer (GC), Phase II results with AstraZeneca's olaparib in breast (BC) and ovarian cancer (OC), and final results from a Phase II trial of OncoGenex Pharmaceuticals' OGX-011 in prostate cancer (PCA).

Specifically, trastuzumab showed unprecedented survival in aggressive GC. Data from the international, Phase III ToGA study demonstrated that adding the drug to standard chemotherapy increases average survival by 26 per cent in patients with HER2-positive advanced and inoperable GC compared to chemotherapy alone. This combination is also particularly beneficial to GC patients whose tumours express higher levels of HER2, increasing their median survival to 16 months. Trastuzumab is already well established as the foundation of care for patients with HER2-positive BC and now, based on the ToGA results, Roche is to seek regulatory approvals for its use in HER2-positive advanced GC.

Separately, olaparib showed potential to make significant impact on outcomes of patients with BRCA-deficient BC and OC. Phase II data for the novel, oral poly (ADP-ribose) polymerase (PARP) inhibitor demonstrated that it is effective and well tolerated in women carrying the BRCA1 or BRCA2 gene mutation with BC or advanced OC. PARP inhibition is being explored as a new therapeutic approach in cancers with impaired DNA repair pathways, one example of which is cancers with BRCA deficiency. Indeed, both studies were selected for inclusion in the 'Best of ASCO' scientific programme.

Finally, it was reported that OGX-011 provides survival benefit to PCA patients. OncoGenex presented final results from a Phase II trial, with analyses indicating a survival benefit in PCA patients treated with the compound in combination with docetaxel compared to docetaxel alone. Patients treated with OGX-011 had a rate of death 51 per cent lower than those treated with docetaxel alone. Scott Cormack, President and CEO of OncoGenex, noted that a 39 per cent reduction in death, consistent with the previously-disclosed preliminary analysis, would be a significant advancement for treatment in this patient population, adding: "the multivariate analysis shows an even greater reduction in death rate than our preliminary data and increases our confidence that we are seeing a real and meaningful survival benefit for patients treated with OGX-011...these data clearly justify advancing to Phase III development, and we expect these data will be key in our partnering discussions for future clinical development and potential commercialisation."

Alice Rossiter - Cancer Drug News Editor