My View on Chinese-Herb Pharmacological Research and *New-Drug* Development
I have worked in TCM teaching and clinical practice for over 40 years; I am not a drug person. The subject I take up today is wholly from the angle of TCM clinical practice and decades of TCM-theoretical research in teaching — a few thoughts.
I have worries of the Qi person about some current research lines and methods of new-drug development. If we set aside TCM's unique theoretical system and use modern technical means — chemistry, physics — only to analyze active components of Chinese herbs, confirm by experiment their pharmacology, efficacy, toxicity, and use these data to win and expand international acceptance, gradually fading the traditional theory of TCM, then in a hundred years abolish-medicine, keep-the-herbs may well be the result. For instance: from wuweizi extract and develop the transaminase-lowering drug Biphenyl; from qingdai the main active Indirubin for chronic granulocytic leukemia; from mahuang, long ago, ephedrine and, by chemical alteration, deoxyephedrine. I do not oppose these methods, but this is not the main path of developing TCM pharmacology by inheriting its theory. And once they become new drugs, they are no longer Chinese drugs — because they are not used under TCM bianzheng shizhi. E.g., TCM treats hepatitis and improves liver function by patient's pathogenesis: heat-clearing toxin-resolving, soothe-liver tonify-kidney, or fortify-spleen — by different pattern, different effective formula. To seek one transaminase-lowering specific does not fit TCM treatment. So I think simply using Western pharmacological mode to analyze Chinese-drug action, abandoning traditional Chinese-drug knowledge, will, over time, risk losing the effective medical character our ancestors built.
I have this view because any science has its own model and system; without them it cannot be a discipline. In the history of a discipline, while in development it may borrow others' lines and methods, but it must never throw away its own — long practice-tested — special system. Only when a discipline's unique system is widely recognized and fully developed does it have unlimited life (e.g., TCM acupuncture: in many countries that have learned it, the channel and point names have aligned with ours). Conversely, when its unique system is not recognized, or has been replaced by other disciplines' modes — when uniqueness has gone — the discipline is at the brink of death.
Chinese medicine and pharmacology, on Chinese soil, under China's historical conditions (society, geography, weather, ideology, life-customs), through thousands of years of practice-cognition-re-practice-re-cognition, has gradually become a fairly complete unique system with rich clinical experience. Today we speak of drugs, but in development medicine and drugs cannot be separated. A physician who does not know drugs cannot be a physician; drugs apart from medical reason must lose their root. Through history, Bencao works were mostly by physicians — well known. The traditional pharmacology of Chinese drugs is unified with TCM basic theory of zàng-xiàng, channels, and clinical li-fa-fang-yao. Summed up as li-fa-fang-yao.
What unique content does traditional Chinese pharmacology have? Nature-and-flavor, channel-attribution, raising-descending-floating-sinking, thick-thin of qi and flavor, daodi (place-of-origin) gathering, seven feelings of preparation — well known in the field. What I want to note: Bencao works (including books containing bencao, e.g. Qianjin Yaofang, Jing Yue Quan Shu · Bencao Zheng), apart from adding or removing species and refining recognition, are basically classified two ways. One: by family — plant, animal, mineral; historically, the majority. The other: by function — surface-releasers, purgers, supplementers ... beginning with Huang Gongxiu's Bencao Qiu Zhen of the Qing. I favor the first. The second seems convenient for clinical drug-choosing but has the defects: classification and content do not match; hard to align with Formula Science. It does not bring out the special feature of Chinese drugs — that their function is not single, and varied function emerges in combination in compound formula. Example: mahuang in function-classified texts is under surface-releasers; in fact, beyond sweating and surface-release, it diffuses lung and calms wheezing, promotes urination. Huangqi is under tonics; besides supplementing qi and lifting yang, securing surface and stopping sweat, it can support sore-and-ulcer healing, promote urination and reduce edema, and clear fever. So although today's research on Chinese-drug pharmacology with modern science (extracting chemical components — even though identifying constituents as the standard of modernization is not wholly accurate) is hard, at least we should not confine ourselves to one single function. Mahuang Tang, Maxing Shigan Tang, Mahuang Shengma Tang, Mahuang Lianqiao Chixiaodou Tang, Yuebi Tang, Yanghe Tang — all use mahuang. Xiao Chaihu Tang, Xiaoyao San, Chaihu Shugan San, Sini San, Buzhong Yiqi Tang, Lianqiao Baidu San — all use chaihu. Danggui Buxue Tang, Buyang Huanwu Tang, Yu Pingfeng San, Zaizao San, Tounong San — all use huangqi. Their pharmacology is not single. If, by this line, modern hi-tech means be used to research persistently, in the near future Chinese pharmacology may shine anew with the age.
On new-drug development. Any unprecedented invention is hard, great, and at first imperfect. Most new things are built on the old. New drugs in modern Chinese-patent medicine are no exception. The question is, with the times, how to let traditional Chinese herbs and their compound preparations have scientific data, be able to be 'said clearly and understood,' fit safety-effectiveness-long-effectiveness (three effectivenesses) and small dose, small toxicity, small side-effect (three smalls), convenient to take, carry, process, transport-and-store, store (five conveniences) (Yang Guang, Discussion on TCM Modernization) — or just chase economic profit. If the former (without excluding profit), I think we should first work hard on inheritance. E.g., the market's Aloe Capsules are in fact from Genyi Pill (更衣丸); Beijing Tongrentang's Weiqi Zhitong Wan is the formula Liangfu Wan. Henan Wanxi Pharmaceutical's Jinkui Shenqi Wan (concentrated pill) line under the Taisheng trademark. This approach meets or approaches the era's requirement and is a short cut to new drug development.
Now new-drug applications require few herbs — right? In the Southern-and-Northern Dynasties, Qi · Chu Cheng's Chushi Yishu recorded: "The best preparation uses one herb; two next; many third. ... To use medicine is like using soldiers, to use a doctor like using a general; the good soldier-user, even with carts only, achieves; the good drug-user, with ginger and cinnamon makes great effect." But long use of one herb, or any imprudent use, has big side-effects, even fatal. Song · Shen Kuo's Mengxi Bitan, On Cautious Drug-Use, records: long use of chuanxiong alone caused sudden death; long use of kushen for tooth cleansing damaged the kidney and made the loins heavy.
I cite these for two reasons. First, in TCM canon there are widely rich, herb-few-and-strong, effective formulas (usually 2–4 herbs) waiting to be discovered. Some traditional patent medicines — proven effective — are no longer produced for economic-process reasons, which is wrong. Second, in long medical practice we have both successes and failures to learn from. If we go this way, investment of effort (with a hard-working scholar's attitude) will be greater; investment of finance will fall a great deal.