There was a placebo-controlled study published in 2005 on Potaba which showed that this drug halted progression of Peyronie’s. Based on this data for those who tolerate Potaba, would this not be a reasonable addition to a verapamil injection and/or verapamil iontophoresis regimen? Would there be any contraindications to this?

You are clearly doing your homework investigating the research on Potaba which was a very well conducted placebo-controlled trial. This study did show stabilization of the disease and some reduction in plaque size in those patients who received Potaba, but there was no evidence of improvement of deformity. In my opinion, if this drug were inexpensive, caused no side effects, and did not require ingesting 24 tablets a day, it may be worth considering. But given that there is no improvement in deformity, in my opinion there is little evidence of benefit with this agent, and the cost, side effects, and large number of tablets make the consumption of the drug inconvenient. I am therefore not a fan of using Potaba at all. There is certainly no contraindication to using this combination with verapamil or interferon injections, but I think other oral agents may make more sense such as pentoxifylline and L-arginine.