Ok, let's go with definitions and what the law says
8 CFR 316.10 Good moral character.
(b) Finding of a lack of good moral character.
(2) An applicant shall be found to lack good moral character if during the statutory period the applicant:
(iii) Violated any law of the United States, any State, or any foreign country relating to a controlled substance, provided that the violation was not a single offense for simple possession of 30 grams or less of marijuana;
Now we have to go with the definitions to know what is a controlled substance
21 USC 802: Definitions
(6) The term "controlled substance" means a drug or other substance, or immediate precursor, included in schedule I, II, III, IV, or V of part B of this subchapter. (...).
I looked at Part B and I saw marihuana in §812 Schedule I (c)(10)
Ok, let's continue looking more definitions in §802:
(44) The term "felony drug offense" means an offense that is punishable by imprisonment for more than one year under any law of the United States or of a State or foreign country that prohibits or restricts conduct relating to narcotic drugs, marihuana, anabolic steroids, or depressant or stimulant substances.
Now we have marihuana mentioned in two different definitions tied to situations that would bar Naturalization.
Let’s see what they consider to be “marihuana”, still in §802:
(16)(A) Subject to subparagraph (B), the term "marihuana" means all parts of the plant Cannabis sativa L., whether growing or not; the seeds thereof; the resin extracted from any part of such plant; and every compound, manufacture, salt, derivative, mixture, or preparation of such plant, its seeds or resin.
(B) The term "marihuana" does not include-
(i) hemp, as defined in section 1639o of title 7; or
(ii) the mature stalks of such plant, fiber produced from such stalks, oil or cake made from the seeds of such plant, any other compound, manufacture, salt, derivative, mixture, or preparation of such mature stalks (except the resin extracted therefrom), fiber, oil, or cake, or the sterilized seed of such plant which is incapable of germination.
So here we have some direct definitions from which you might be able to tell if your situation would fall within that category or not. Let's just make sure we have the definition of hemp, which is one of that exclusions:
7 USC 1639o: Definitions
(1) Hemp
The term "hemp" means the plant Cannabis sativa L. and any part of that plant, including the seeds thereof and all derivatives, extracts, cannabinoids, isomers, acids, salts, and salts of isomers, whether growing or not, with a delta-9 tetrahydrocannabinol concentration of not more than 0.3 percent on a dry weight basis.
Well, CBD products usually fall into that hemp category (not marihuana, not a controlled substance). However, you mentioned that there’s medical marijuana research. So I’d presume that it’s not CBD, but THC or other endocannabinoids (which are not mentioned, thus not controlled). A Biopharmaceutical company usually likes to stay on the good side of the law, and probably have the necessary permits to do research on controlled substances (remember, controlled substances are the bread and butter of pharmaceutical companies).
I could not find the specific law, cos it would require more digging, but you can see from this report (https://crsreports.congress.gov/product/pdf/IN/IN11503) that “The Schedule I status of marijuana means that it is strictly regulated by federal authorities, regardless of state regulations and laws, and its growth, distribution, and possession (regardless of recreational or medicinal purposes) are prohibited under federal law aside from activities related to lawful research”
Otherwise, anyone working for almost every pharmaceutical ever or lab would be in big trouble.
If you are not comfortable or used to read and understand laws (or think your company is doing unlawful research), seek legal council.