Herbal drugs constitute essential and important components of the vast knowledge pertaining to traditional medicines that India has been garnering for thousands of years. Interestingly, the last few decades have witnessed a steep rise in the employment of herbal medicines for the alleviation of a number of disease conditions, ranging from simple fever to more severe conditions like diabetes to life-threatening conditions like cancer. The growing market for herbal drugs, which has essentially stemmed from the high cost and harmful side effects of the widely used synthetic medicines, is evident not only in our country but also in the developed countries across the globe.
In this respect, India has been blessed with a rich heritage and traditional knowledge about herbal medicines. Our country exhibits a huge biodiversity, with more than 25,000 herbal formulations being prescribed by more than a million and a half practitioners relying on traditional medicines to cure various diseases. Despite a large sector of industry devoted to the production of herbal medicines, our country accounts for a dismal share in the world market with regards to the export of crude plant extracts and drugs. This lag experienced by the Indian herbal medicine industry may be largely attributed to the poor product quality or to improper use. There exists a stark lack of an adequate regulatory framework and suitable quality control systems to facilitate herbal medicines of appropriate quality. Despite several initiatives by The World Health organization (WHO) to strengthen national regulation, registration, quality assurance and control of herbal medicines, the collective efforts to achieve these goals are progressing at snailâs pace. This manuscript highlights the existing gaps and the urgent need for establishing research standards in ayurvedic and herbal medicines, so as to increase their acceptance in the scientific community and equip them for a healthy competition with the mainstream modern medicines.
Pharmacovigilance requirements in Ayurveda Medicines
India has been practicing the science of Ayurveda and the other traditional systems of medicine for centuries and its drugs are rated as one of the safest cures. However, the Ayurveda, Siddha and Unani (ASU) systems, possess fewer evidences for precisely proving their efficacy and safety. The scientific acceptance of such medicines will thus require ample clinical data to confirm their safety and effectiveness. This warrants for a suitable pharmacovigilance system to afford the necessary credibility to Ayurveda and other traditional systems of medicines. One of the primary aims of such a system will be to prevent any adverse drug reaction (ADR) arising from the herbal drug used to cure, treat or diagnose a disease and to establish acceptable doses which may provide a fair balance between efficacy and toxicity. Establishment of such internationally acceptable pharmacovigilance mechanisms will thus contribute significantly to scientifically attest the parity between the herbal drugs and modern medicines.
Ayurveda, being practiced for thousands of years, has references to the safety and efficacy of individual drugs in classical texts. It was the pioneer medicinal system that considered the possibility of ADRs and incorporated a system to avoid or nullify them. Ayurveda even categorizes its medicines based on its toxicity and describes the thorough management of possible ADRs. However to scientifically prove the safety of these systems, a comprehensive data based on the clinical and pharmacological studies needs to be generated. It is a common misconception that Ayurvedic drugs are devoid of any side effects. However it should be acknowledged that no drug could be absolutely devoid of toxicity and those that are will seldom have any desirable effect. In this context, it becomes necessary to assess the safety of an administered drug and determine suitable doses and dosage regimens, which will yield the desirable action while obviating the toxic effects.
Ayurveda and other traditional medicinal systems primarily focus on the synergistic effect of multiple ingredients, unlike the dependence on a single Active Pharmaceutical Ingredient (API) in their modern counterpart. Hence the prognosis of ADRs in herbal medicines is difficult. Many herbal medicines are also used in combination with other drugs. Such combination therapies also need to be evaluated and monitored for the possible ADRs. Such issues require careful attention through strengthening of pharmacovigilance systems. Establishment of National Pharmacovigilance Centers with employees possessing specific technical expertise are thus necessary to provide herbal drugs with better safety, quality and efficacy and include them in the ambit of pharmaceutical industry. Furthermore, the National Pharmocovigilance systems should closely work and in conjunction with The National Drug Regulatory Systems, to establish reports and database recording the efficacy and adverse effects of herbal medicines.
India has already taken certain steps in this direction. After the emphasis of WHO to include traditional medicines under the pharmacovigilance system, our country has published the guidelines on safety and monitoring of herbal medicines in 2004. Ayurvedic, Siddha and Unani drugs have been included in the national pharmacovigilance program after the initiative of Ministry of Health and Family Welfare, Government of India. A technical committee, namely the National Phamacovigilance Technical Advisory Committee (NPTAC-ASU), has been constituted to review and analyze the reported ADRs and suggest appropriate remedial measures.
However, these measures with regards to the policy-making are still met with significant drawbacks. Despite encouragement from the national pharmacovigilance program to report the ADRs, the numbers of reports that are flagged are very low. This also requires awareness amongst the large number of traditional medicine practitioners to promptly report such occurrences. The communication gap between the medical practitioners and policy makers needs to be lessened to establish appropriate governance regulations for traditional medicines. The industry on the other hand needs to focus on generating databank of safety data as well as pre-and post marketing reports of traditional medicines. It is also necessary to include exposure to traditional medicines in the educational system, to develop a strong human resource motivated towards and dedicated to the success of this enterprise.
Equivalent trial design
Traditional medicines, particularly the Ayurvedic drugs, have always drawn immense attention for their reduced side effects and safety as compared to the synthetic medicines. Though safety is of utmost importance, efficacy is the area where modern medicines have scored better. Clinical trials with modern medicines primarily rely on the efficacies of the drug, which are commonly concluded based on the randomized double-blinded placebo controlled method. However, a more rational approach would be to prove the superior efficacy of new molecules by testing with a comparable molecule rather than by using placebo as a control. This way, a new molecule would be proven to match the efficacy of an existing drug and its other advantages like cost, safety etc. may be taken into consideration. Thus, there is a need to bring about an equivalent trial design which would not only improve the present standard but will also provide a better platform for herbal drugs to compete with modern medicines.
Need for Systematic and Strong Government Initiatives
There is a lack of collective and systematic efforts in furthering the research growth of Ayurveda and other traditional medicines in India. Numerous initiatives were introduced to promote research in this field, but the lack of consistency in investigations and results has lead to a decline in this enthusiasm. The National Millennium Indian Technology Leadership Initiative was one major landmark, started in 2003, which gave several grants to research institutes to foster growth in herbal medicines. Today, 10 years since its inception, no significant breakthroughs or achievements have been reported.
Our nearest neighbor, China, on the other hand has made significant advances in establishing standards in their Traditional Chinese Medicine (TCM) in the past few years. Seeing their dynamic growth, economic leaders like USA have lent a helping hand to further the prospects of TCM. An excellent example of this is the collaboration of Chinese Universities with Harvard University, in 2009, in developing a natural extract database of extremely high standards. These sort of rigorous and systematic efforts are still missing in India. This warrants for systematic and stronger initiatives on behalf of Government and Pharmaceutical Industries to boost the academic research to provide scientific equivalence between traditional and modern medicines.
Unique Evaluation Scale
The standard evaluation scale of clinical trial experiments for modern medicines involves studying the effects of an ingredient or a combination of few ingredients on a physiological condition. This methodology would be suitable and ideal in cases where the ingredients to be studied are limited (in case of one/few APIs). This scenario is completely different for ayurvedic and other herbal medicines. Herbal medicines frequently involve usage of multiple herbs and sometimes an entire plant for preparation of suitable extracts for relieving particular disease conditions. The methods of formulation development, the diagnostic criteria utilized and other parameters used to determine their end-benefits, are significantly different from the ones followed in modern medicine. It is also impossible to establish a complete translation of all Ayurvedic and other traditional system derived terminologies into equivalent terms of modern medicine. Hence, ideally herbal drugs should have a different scale of measurement to bring them at par with modern medicine. This has to be systematically and collectively framed so that the advantages of herbal medicines are intact and at the same time high standards are maintained.
The Road Ahead
In the wake of afore-mentioned scenario, the best way forward would be to establish appropriate standards in traditional medicine clinical research and to delve in efforts towards their global harmonization. To begin with, the physicians and researchers in the field should engage in setting up standards via thorough understanding and complete utilization of diagnostic principles based on traditional medicinal systems. Inspirations could be drawn from the success of modern medicine, but at the same time separate and distinct standards should be created for the herbal medicines, due to their inherent differences as compared to the former. Modern medicines have undoubtedly relieved symptomatic pain from the life of many suffering people and have provided new therapeutic strategies, time and again. However, at the same time it should be noted that the herbal medicines and Ayurveda have also stood the test of time with their unique and holistic approach of treatment. A better standardization strategy would thus keep them in good pace and ensure their universal acceptance. This may also pave a way for integration of traditional and modern medicines in the future. Methodical, dedicated and synchronized efforts from physicians and experts in traditional and modern medicine thus constitutes the need of this hour to further the prospects of medical science at large.