new research: ICON7 Results May Change Practice in Ovarian Cancer

Dr. Andrés Cervantes: ICON7 Results May Change Practice in Ovarian Cancer
OncologySTAT Editorial Team. 2010 Oct 25, Interview by L Scott Zoeller
Andrés Cervantes, MD, PhD, is Chair of the Educational Program for the 2010 Congress of the European Society of Medical Oncology (ESMO).

OncologySTAT: Dr. Cervantes, what were the most important studies in ovarian cancer that were presented at this year’s ESMO Congress?

Dr. Andres Cervantes: For me, the most important study was the ICON7 trial, which was presented during the presidential session of the ESMO Congress.1 It was a very important presentation because the paper is the result of a randomized phase III trial by a large cooperative group. The study was done within the Gynaecologic Cancer InterGroup, with an effort of several other cooperative groups, including the British MRC/NCRI, the leading group. However, also involved were the German AGO-OVAR, the Australian and New Zealand ANZGOG, the Spanish group for research in gynecologic and ovarian cancer, GEICO, the French GINECO, the Scandinavian group NSGO, and the National Cancer Institute of Canada, NCIC.

A total of 263 sites participated in the trial. This is one of the most impressive randomized trials in ovarian cancer, accruing more than 1500 patients over 2 years. The trial was designed with a primary endpoint of progression-free survival (PFS). The control arm was conventional carboplatin/paclitaxel treatment given for 6 courses. The experimental arm was the same treatment plus the addition of bevacizumab, for a total of 18 courses (ie, meaning a bit more than 1-year duration).

This trial was mature enough to report results because the number of progressive disease events needed to achieve 90% power was reached. The study showed that the addition of bevacizumab to chemotherapy significantly prolonged PFS. Median PFS was 19 months for the experimental arm and 17.3 months for the control arm (hazard ratio [HR], 0.81, P =.004), suggesting very strong statistical significance.

The trial is also intended to demonstrate differences in overall survival (OS). However, the number of events is still insufficient for the OS analysis. Only 16% of patients included in this trial have died. In the beginning of 2012 we will be able to present the final results with survival data.

I would stress the importance of ICON7 in that it confirms the results of the Gynecologic Oncology Group (GOG) 218 trial that were presented at the ASCO meeting in June.2 The GOG 218 trial also showed that the addition of bevacizumab to chemotherapy in the treatment of ovarian cancer patients leads to longer PFS.

In the discussion at the presidential session, Dr. Michael Bookman indicated how similar the GOG 218 results were compared with those of the GOG American trial. Dr. Bookman also made some comparisons of the study designs which were a bit different.

No new first-line drug has been introduced that has been able to modify the natural history of ovarian cancer since the approval of paclitaxel in 1996. In light of this, I consider these trials to be very important.

Several randomized trials were also presented in the oral sessions for gynecologic tumors. I think a very important one is a phase II randomized trial on olaparib, which is a PARP inhibitor, compared with pegylated liposomal doxorubicin (PLD) in ovarian cancer patients with BRCA1 or BRCA2 mutations.3

This trial compared 2 doses of olaparib, 200 mg twice daily or 400 mg twice daily, given orally continuously in 28-day courses, with pegylated liposomal doxorubicin, the standard of care for patients with advanced ovarian cancer relapsing after first-line platinum-based therapy.

The trial was properly designed and conducted. The number of patients was very limited; fewer than 100 patients were included. Although, the final results indicated no significant difference in PFS between the two olaparib arms and the PLD arm, the number of objective responses was slightly higher with olaparib 400 mg twice daily. I think the use of PARP inhibitors in ovarian cancer still requires further study.

A phase III randomized trial on the use of epothilones in ovarian cancer, although negative, was significant because it adds to our body of knowledge.4 The trial confirmed that the addition of patupilone to treatment for refractory ovarian cancer is of no benefit. However, even though the trial has no implications for practice, it was a study that the medical and oncology community had been waiting for, and, so, the results were important in that respect. This is good science.

References

1. ICON7. A phase III randomised Gynaecologic Cancer InterGroup trial of concurrent bevacizumab and chemotherapy followed by maintenance bevacizumab, versus chemotherapy alone in women with newly diagnosed epithelial ovarian (EOC), primary peritoneal (PPC) or fallopian tube cancer (FTC). Paper presented at: 35th European Society for Medical Oncology (ESMO) Congress; October 8-12, 2010; Milan, Italy. Perren T, UK, Presenter. Abstract LBA4.

2. Burger RA, Brady MF, Bookman MA, et al. Safety and subgroup efficacy analyses in GOG218, a phase III trial of bevacizumab (BEV) in the primary treatment of advanced epithelial ovarian cancer (EOC), primary peritoneal cancer (PPC) or fallopian tube cancer (FTC): a Gynecologic Oncology Group study. Paper presented at: 35th European Society for Medical Oncology (ESMO) Congress; October 8-12, 2010; Milan, Italy. Proffered Paper 978.4.

3. Kaye S, Kaufman B, Lubinski J, et al. Phase II study of the oral PARP inhibitor olaparib (AZD2281) versus liposomal doxorubicin in ovarian cancer patients with BRCA1 and/or BRCA2 mutations. Paper presented at: 35th European Society for Medical Oncology (ESMO) Congress; October 8-12, 2010; Milan, Italy. Proffered Paper 9710.

4. Colombo N, Schwartz PE, Bamias A, et al. Results of a randomized, open-label, phase III trial of patupilone (P) versus pegylated liposomal doxorubicin (PLD) in taxane/platinum refractory/resistant patients with recurrent ovarian, fallopian, or peritoneal cancer. Paper presented at: 35th European Society for Medical Oncology (ESMO) Congress; October 8-12, 2010; Milan, Italy. Abstract LBA24.