This combination seems too good to be true. Fifty-seven patients with episodic migraine, meaning 14 or less attacks per month, were given Zocor (simvastatin) 20 mg and vitamin D3 1000 units twice daily. The treatment group had a very high reduction of 8 migraine days per month compared to only 1 in the placebo group. Twenty-five percent of patients in the treatment group had a 50% reduction in headache days compared to only 1 patient (3%) in the placebo group. As expected, adverse effects were similar in both groups. This was a small study and needs to be replicated, but the treatment effect seems very high and placebo effect very low. This low placebo effect is unusual in migraine studies, as it is usually higher.
See Annals of Neurology, 2015, with lead author Buettner.