CARA, GWPH, ZYNE are listed on NASDAQ. Each, especially GWPH, has significant cash reserves to conduct research. Each has conducted secondary offerings to raise additional capital, which is quite different from the OTC reefer scam stocks with a medical angle. They resort to convertible debt offerings, except they often attempt to disguise this fact in the potboiler filings with the SEC.
To my knowledge, no American public stock company has created an effective treatment using either synthetic compounds or natural compounds that would pass muster with the US Food and Drug Administration.