Get our free Vandetanib coupon and be eligible to receive a discount. You can reduce your Vandetanib cost by up to 75% with our free Vandetanib discount card. Bring it to a participating pharmacy near you to save on your prescription medication.Vandetanib is a cancer medication that interferes with the growth of cancer cells and slows their spread in the body. Vandetanib is used to treat thyroid cancer. Vandetanib may also be used for purposes not listed in this medication guide.