Jon,
Thank you for the kind words. I've been in touch with the Principal Investigator for the vitamin D3 migraine prophylaxis RCT. He and his team are working the final manuscript for publication. Once that's out of the way and they can find the funding, a follow-on RCT using a vitamin D3 physiological dose of 10,000 IU/day is on their list of things to do.
There's a good reason why the mAb RCTs can't achieve better efficacy. When you consider the site of action are neurons within the brain that produce calcitonin gene-related peptide (CGRP) and mechanism of action they espouse is neutralization of CGRP, the first step in these two processes is getting the mAb into the brain. That's a very real problem Big Pharma has yet to solve. The maximum opening size through the tightly packed endothelial cells forming the blood brain barrier (BBB) is a molecular mass of 400 Da (Daltons). The mAbs have a molecular mass of 150 kDa (150,000 Da)... 375 times larger than openings through the BBB. If the mAbs cannot pass through the BBB to enter neurons throughout the brain, neutralizing CGRP within these neurons is a non-starter. My guess is the reduction in migraine days made possible with mAbs is due to reducing serum CGRP.
For reference, vitamin D3 has a molecular mass of 385 Da so passes readily through the BBB and into neurons where it's hydroxylated by enzymes to 1,25(OH)2D3, the genetically active vitamin D3 metabolite. It in turn attaches to Vitamin D Receptors (VDR) at the genetic layer initiating the genetic expression that down-regulates CGRP expression... and in the process, prevents our CH and MH. Better living through chemistry... and molecular biology... That's my SWAG... and I'll stick with it until a better mechanism of action is found.
Take care,
V/R, Batch