A Clinical Trial Evaluating the Efficacy of Valganciclovir in Glioblastoma Patients

Inclusion Criteria: 1. Patients aged 18 years or older 2. Patients with newly diagnosed glioblastoma, IDH 1 wt, WHO grade IV 3. Radical resection 4. Concomitant treatment with temozolomide and radiation therapy 5. MGMT promoter methylation status 6. Patients with at least KPS 70 , ECOG/WHO 2 7. Patients providing written informed consent 8. Patients cooperative and able to complete all the assessment procedures. 9. Females of child-bearing age must have a negative pregnancy test at screening (all premenopausal women, or in case when menstrual status can not be ascertained in women under the age of 55). Female patient must agree to utilize a highly efficient birth control method throughout the study period (Pearl index \<1, e.g: oral contraception with gestagens, transdermal contraceptives, implants, injectables, intrauterine devices, bilateral tubal occlusion, sexual abstinence or vasectomised partner). The birth control method must be used at least 30 days after treatment end. Pregnancy testing should be performed at monthly intervals due to high teratogenic potential of valganciclovir. Men are recommended to use condoms with female partners during, and for at least 90 days following treatment with Valganciclovir. 10. Patients must be enrolled within 10 weeks after surgery Exclusion Criteria: 1. Patients allergic to, or who do not tolerate Valganciclovir, aciclovir or valaciclovir treatment 2. Patients with decreased cognitive function (below 24 in MMSE test) 3. Pregnant or lactating females 4. Patients not signing informed consent 5. Patient is simultaneously participating in another experimental drug therapy trial 6. Neutrophil count \< 1,5 cells/ 109/L 7. Platelet count \< 150 cells/ 109/L 8. HGB \< 80 g/L 9. Abnormal renal function (GFR \< 30) 10. Secondary glioblastoma, or glioblastoma IDH1 mutated. 11. Unfit for any other reason judged by investigator