Last week the American Society of Clinical Oncology (ASCO) held a press briefing to highlight some of the studies at the forthcoming annual meeting in Chicago next month.
ASCO president, Dr George Sledge of Indiana, announced that the meeting theme for this year is “Patients, Pathways, Progress” to reflect the growing focus on molecular targets to identify and treat patients more effectively.
Traditionally, ASCO has organised their meeting around tumour types such as breast, lung, prostate and colon cancers, for example, but this year I was delighted to see that the Developmental Therapeutics section is getting more attention with a greater focus on the molecular targets that are now emerging:
Of the abstracts covered in the briefing, two in particular really stood out for me. One was on Exelixis’ cabozantinib (XL184) in bone metastases, which my colleague wrote about on Biotech Strategy Blog and the other was the data for AstraZeneca’s PARP inhibitor, olaparib, in serous ovarian cancer.
Many of you will know that I’ve been covering PARP inhibitors on this blog since 2006 – although they have had somewhat of a chequered history to date. After the recent failure of Sanofi’s iniparib in triple negative breast cancer and AstraZeneca deciding to put a phase III breast cancer trial on hold while they reformulate the drug from capsules to a tablet to make it easier for people to take, many weren’t sure what was happening with the PARP class of compounds.
Would they be consigned to the drug dustbin or would they come back from the dead?
Dr Jonathan Ledermann (University College London) presented an overview of the phase II results in serous ovarian cancer. These were women both with, and without, the BRCA gene. It has previously been shown by Audeh et al., (2010) that ~30% of inherited BRCA mutated tumours respond to PARP inhibitors, particularly those that have ‘platinum-sensitive’ disease.
Here is the phase II study design in serous ovarian cancer:
What was in interesting in this study was that, overall, Dr Ledermann noted that they found that women in the olaparib arm lived for 8.4 months before progression, compared to 4.8 months on placebo. This 3.6 month improvement in PFS was statistically significant.
We will know more about the details of this study on Saturday 4th June at ASCO, but for now, two things stand out:
- This is the first study to demonstrate a statistically significant benefit of maintenance treatment for ‘platinum-sensitive’ relapsed serous ovarian cancer
- 50% of olaparib and 16% of placebo patients were still on treatment at the time of the analysis
These results seem pretty compelling and important to me.
If you’re around at ASCO on Saturday, the ovarian cancer session is on from 3-6pm in room E354a – check it out!
For those interested, there are also some new data being presented on Abbott’s PARP inhibitor, ABT-888 (veliparib) combined with temozolomide in refractory colorectal cancer. This is also on Saturday afternoon from 4.30-6pm in the Clinical Science Symposium in Hall D1.
No doubt many of us will be running around up and down the escalators on the very first day, some Segways with hooters might help! Still, I dream/long for the future when ASCO follows AACR’s lead and organises sessions around molecular targets and pathways instead of tumour types… maybe that won’t be too far into the future after all 🙂
Audeh, M., Carmichael, J., Penson, R., Friedlander, M., Powell, B., Bell-McGuinn, K., Scott, C., Weitzel, J., Oaknin, A., Loman, N., Lu, K., Schmutzler, R., Matulonis, U., Wickens, M., & Tutt, A. (2010). Oral poly(ADP-ribose) polymerase inhibitor olaparib in patients with BRCA1 or BRCA2 mutations and recurrent ovarian cancer: a proof-of-concept trial The Lancet, 376 (9737), 245-251 DOI: 10.1016/S0140-6736(10)60893-8