I have been on Avastin (mvasi) for over 5 years on and off. I would always get a stiff neck where I couldn't turn my head, aches in legs, and lose function in my wrists and grip strength. I had read up on the studies regarding Metformin to help with chemo side effects and asked my oncologist if I could give it a try. He agreed and said it may not do anything but it won't hurt to try. I am not diabetic. After 3 months on Metformin all the aches were gone. Nothing else had changed in my treatment and my activity level was the same. At the time I was on taxol, carbo and Avastin. I know there's not that many studies out there but it worked for me.