SOLO1: 7-Year Follow-up Highlights the Value of Maintenance Olaparib

Maurie Markman, MD


December 12, 2022

This transcript has been edited for clarity.

I'm Dr Maurie Markman from Cancer Treatment Centers of America. I want to discuss a very interesting paper that recently appeared in the Journal of Clinical Oncology, entitled, "Overall Survival With Maintenance Olaparib at a 7-Year Follow-up in Patients With Newly Diagnosed Advanced Ovarian Cancer and a BRCA Mutation: The SOLO1/GOG 3004 Trial."

Most of you probably know the results of the SOLO1 study, which appeared in The New England Journal Medicine a number of years ago. It demonstrated the very impressive value of olaparib maintenance therapy in the short term, reporting progression-free and overall survival in patients with advanced ovarian cancer — again, used in maintenance — with a BRCA mutation.

This particular paper, however, with a 7-year follow-up, begins to address a very important question: What about long-term follow-up?

This was a randomized, double blind, placebo-controlled study. Patients with newly diagnosed advanced ovarian cancer who achieved a clinical response and had a documented BRCA mutation, either germline or somatic, were randomized to olaparib maintenance at the completion of platinum-based chemotherapy or placebo.

Placebo or olaparib could be continued up to a maximum of 2 years. Some patients had the opportunity, with the agreement of the principal investigator, of longer than 2 years, but basically 2 years of maintenance therapy with olaparib or placebo.

This question of long-term follow-up survival was addressed in the paper. The median duration of treatment with olaparib on this trial was 24.6 months, as anticipated, and was 13.9 months with placebo. The median follow-up of this patient population was 88 months, which is longer than 7 years.

The total sample size of the olaparib-treated patients was 260, and of the placebo-treated patients, 131. The bottom line is that at a 7-year follow-up, 67% of the patients who received olaparib were alive vs 46.5% of the placebo-treated patients. Again, this was a maintenance phase. There was basically a 20% higher absolute number of patients who were alive who received olaparib vs placebo.

Looked at another way, at this particular point in time, at 7-year follow-up, 45.3% of patients who had received olaparib were alive and had not received a subsequent treatment regimen. In other words, they were alive and they were still on follow-up without getting another anticancer therapy.

So 45.3% — almost half — of the patients who received olaparib had not received any further therapy vs 20.6% of patients receiving placebo who were alive and had not received any further therapy. That is, the placebo-treated patients had half the probability of remaining [alive] without any further therapy. Among the olaparib-treated patients, again, almost half had no further therapy at a follow-up of 7 years.

In addition, and very importantly, the study, with long-term follow-up, showed a very low risk for myelodysplastic syndrome or acute leukemia, which was a concern with PARP inhibitors. There were no new primaries or safety concerns with this long-term follow-up.

This study, SOLO1, again emphasized this point. Long-term follow-up survival data demonstrated the value of maintenance olaparib after an initial response to platinum-based chemotherapy in women with a BRCA mutation. There is no question that there is major value in this patient population.

For those of you interested in this topic and the management of ovarian cancer, or patients or family who are interested in this particular question, I refer you to this very important study, recently published in the Journal of Clinical Oncology. Thank you for your attention.

Maurie Markman, MD, is president of medicine and science at Cancer Treatment Centers of America in Philadelphia. He has more than 20 years of experience in cancer treatment and gynecologic oncology research.

Follow Medscape on Facebook, Twitter, Instagram, and YouTube


Comments on Medscape are moderated and should be professional in tone and on topic. You must declare any conflicts of interest related to your comments and responses. Please see our Commenting Guide for further information. We reserve the right to remove posts at our sole discretion.