E. Drug R&D 101

Endogenous Roots of a Drug

March 21, 2023

Including amino acids, vitamins, and molecular substances produced by or related to the human microbiotas, endogenous molecules are the most abundant source to identify the efficacies of commercial drugs to date. The evidence to support this statement is that nearly every effective drug on the market can find at least a full or partial endogenous molecular match in terms of its therapeutic functions. Sometimes, the correspondence to a single drug consists of numerous endogenous molecules in many categories, such as oncology, dementia, diabetes, and infectious diseases. This phenomenon is also consistent with the reasoning that local or global instability of homeostasis in the human body is the cause of a disease, and a drug plays an assistant role in stability recovery by enhancing innate responses from the defense system, such as the immune system. In other words, the role of a drug is rooted in the need of its family members in the biosystem of humans.

For drug R&D, some endogenous molecules deserve special attention because each of them is produced in the body on a constant basis and directly linked to many commercial drugs in different therapeutic categories. For example, a well-known endogenous molecule is the full match of thirteen different drug molecules in the following sixteen categories

       (1) Non-small cell lung cancer: two drugs

       (2) Small cell lung cancer: one drug

       (3) Pancreatic cancer and bladder cancer: one drug

       (4) Soft tissue sarcoma: one drug

       (5) Anemia with myelofibrosis: one drug

       (6) Ovarian cancer: one drug

       (7) Liver cancer: one drug

       (8) Bronchiectasis, tuberculosis, and antibiotics: one drug

       (9) Asthma: one drug

       (10) Depression: one drug

       (11) Anticoagulant and hypertriglyceridemia: one drug

       (12) Anti-inflammation: One drug.

A full match between two drug-related molecules means that their targets and target zones where drugs hunt for targets are nearly identical to each other regardless of their difference in solubility. In a general sense of quantitative and precise descriptions, additionally, the strength that a drug attacks targets and its ability to anchor on the target zones are two important criteria for evaluation of its consequential performance, and the details are illustrated elsewhere.

From the above list, one can tell how critical this endogenous molecule is to human health, extending to longevity, antiaging, disease prevention, and so on. It follows that naturally-born and coexistent molecules in humans, such as proteins/peptides, hormones, fatty acids, enzymes, and substances from microbiotas, establish an indispensable foundation for drug R&D.