Add-on valganciclovir yields survival gains in glioblastoma

Use of the antiviral drug valganciclovir as an adjunct to standard therapy in patients with newly diagnosed glioblastoma appears to prolong survival, even in the presence of an unmethylated MGMT promoter gene and regardless of when given after surgery, according to the results of an experimental study.

The study included 102 patients (median age, 59 years; 71 percent male) who were given valganciclovir as add-on to standard therapy and 231 controls (median age, 63 years; 62.8 percent male) who did not receive the add-on. Most of the patients received long-term treatment with the antiviral drug (median, 15.6 months), with only 16 patients receiving 6 months of therapy or less.

Valganciclovir treatment was discontinued due to haematological toxicity in six patients, skin rash in two, myocardial ischaemia in one (not related to treatment), infection in three, and diarrhoea in one. No additional toxicity was observed.

Compared with controls, patients who received the antiviral drug had significantly better overall survival (median, 24.1 vs 13.3 months; p<0.0001), higher 2-year survival rate (49.8 percent vs 17.3 percent), and longer time-to-tumour progression (median, 9.9 vs 7.3 months; p=0.0003).

The survival benefits conferred by valganciclovir were observed in patients with radical or partial resection and those with an unmethylated or methylated MGMT promoter gene.

The findings are expected to prompt further investigation into the role of cytomegalovirus in the pathogenesis of glioblastoma.