COQ10 and Vitamin E for Off-Target Radiation Toxicity

The purpose of this study is to determine if high-dose supplementation with the antioxidants Coenzyme Q10 (ubidecarenone) and Vitamin E (dl-α-tocopherol) reduces subacute and chronic radiation-associated toxicity after radiation therapy for pelvic cancers including post-prostatectomy prostate, endometrial, cervical, and anal malignancies. Changes to oncologic outcomes will be assessed to characterize the effects of the vitamin regimen. The safety and tolerability of the vitamin regimen will be tested to determine the recommended phase II dose. Subsequently, the regimen's efficacy towards reducing the incidence and severity of post-treatment toxicity burden will be compared to historical norms. Other objectives of the research include characterizing the trajectory of recovery, patient reported quality of life outcomes, adherence to therapy, and longitudinal changes in biomarkers of oxidative stress. Exposure to radiation can cause sustained oxidative stress, mitochondrial dysfunction, chronic inflammation, membrane injury, maladaptive tissue remodeling, and ferroptosis. The biological drivers of these effects may be counteracted by increasing the pool of active vitamin E (oxidized α-tocopherol) in affected tissues through perfusion and regeneration by CoQ10 (ubidecarenone as ubiquinol). The subject population will include adults with ECOG performance status ≤2 scheduled for curative-intent external beam radiation therapy ± chemotherapy as treatment for the pelvic malignancies listed above. Participants must be able to swallow gel capsules. Known comorbidities that affect vitamin absorption or tolerability, increase bleeding risk, and/or increase the risk of vitamin E overdose may exclude participation. Prior to the initiation of vitamin therapy, participants must complete at least 80% of their scheduled radiation dose and have adequate hematological, organ and clotting function. Pregnancy, lactation, and refusal of contraceptive precautions (unless exempt) preclude participation. Research interventions include daily co-administration of vitamin E (450-900 mg) and CoQ10 (100-200 mg) for 90 days immediately following radiation therapy, frequent clinic visits and phlebotomy, PRO questionnaires, and the collection of blood-based research specimens. The duration of participation will vary with the length of radiation therapy but will always involve a 3-month treatment period followed by 21 months of follow up.