Understand how clinical trial costs and insurance coverage work.
This is straightforward: you never pay for the experimental treatment itself. The sponsoring company or institution provides the drug at no cost to you. That's true of all legitimate clinical trials.
Once the trial ends, things get more complicated (see below). But while you're in the trial, the drug is free.
Many trials cover the cost of visits, lab work, scans, and other tests related to the trial. They should. But coverage varies, and you should ask before enrolling. Some trials cover everything. Some cover some things. Some ask the participant's insurance to cover certain things.
This is why you ask, in detail, what costs the trial covers and what your insurance will be billed for.
Many trials also reimburse travel, parking, or meals. Ask about this too. If you're traveling to a distant trial site, reimbursement can matter.
Your health insurance is required to cover standard care and routine medical care while you're in a clinical trial. The Affordable Care Act mandates this. If you need blood work to check for side effects, insurance should cover it. If you need imaging to monitor the trial's effectiveness, insurance should cover it.
Your current medications unrelated to the trial should still be covered by insurance. Your regular doctor visits should be covered. Basically, the insurance coverage you have now continues.
The one exception: the experimental drug itself is not billed to insurance. The sponsor covers that.
If the drug doesn't work or the trial ends, accessing the drug afterward depends on several factors. If the drug is approved by the FDA, you can get it through normal prescription channels (and your insurance situation applies). If the drug is still experimental, you might be eligible for an expanded access program, which allows continued access before final approval. But access isn't guaranteed, and there may be costs involved.
This is critical: ask before you enroll what happens if the treatment works. Will you have continued access? At what cost? What if you want to continue but the trial sponsor doesn't offer an extended access program? Knowing the answer before you enroll prevents a devastating surprise later.