The combination therapy of Velcade (bortezomib), melphalan (Alkeran), and prednisone, commonly referred to as VMP, extends overall survival in newly diagnosed multiple myeloma patients, compared to melphalan-prednisone (MP) therapy, even after prolonged follow-up and extensive subsequent therapy. Researchers also found that VMP did not increase resistance to subsequent therapy.

The Phase 3 clinical trial, known as VISTA, had shown that VMP therapy improved outcomes in newly diagnosed multiple myeloma patients compared to MP therapy. In particular, patients on VMP showed better response and longer overall survival than patients on MP.

However, the follow-up time associated with the first report of trial results was short (median of 16.3 months).

In the recent follow-up report, the researchers analyzed the trial data after a median follow-up time of 36.7 months to see if the initial results could be confirmed after prolonged follow-up and after the use of subsequent therapies.

The VISTA trial included 682 newly diagnosed multiple myeloma patients who were ineligible for stem cell transplants. The median age of the patients was 71 years, and 30 percent were older than 75 years.

Patients received up to nine 6-week cycles of VMP or MP. 

At the median follow-up time of 36.7 months, overall survival continued to be longer for patients on VMP than for patients on MP. Patients on VMP had a 35 percent higher chance of survival than patients on MP.

Three-year overall survival was 69 percent for patients on VMP, compared to 54 percent for patients on MP. The median overall survival had not been reached yet in patients on VMP compared to 43 months in patients on MP.

Patients continued to be followed after completion of their VMP or MP treatment.

Patients on VMP had a longer treatment-free interval than patients on MP (17.6 months vs. 8.4 months). Among the patients on VMP, 43 percent had a treatment-free interval that was longer than two years compared to 18 percent of patients on MP.

The response rates to subsequent therapy were similar between patients on VMP and MP, indicating that Velcade does not increase resistance to subsequent therapy.

Median survival from the start of subsequent therapy was 30 months for patients who had previously received VMP and 22 months for patients who previously were on MP.

Researchers observed more side effects with VMP treatment than with MP treatment during treatment cycles 1 to 4. Side effects with VMP decreased during cycles 5 to 9 and were similar to side effects with MP treatment.

The rate of VMP treatment-induced nerve damage remained the same during the extended follow-up period as compared to the initial analysis. Researchers found that after prolonged follow-up, 79 percent of nerve damage improved within a median of 1.9 months, and 60 percent disappeared after a median of 5.7 months.

Based on their findings, the researchers suggested using VMP as first-line treatment instead of saving it for after conventional chemotherapy.

For more information, please see the follow-up report in the Journal of Clinical Oncology (abstract).