Readers’ Comments
It is time for another circle of
comments from readers of this Column. The article on Diabetes elicited
interests and reactions, the major one came from Dr. Ismail Zubairu, a medical
practitioner with Ahmadu Bello University Teaching Hospital Shika. He expatiated
on the “reverse pharmacology” as a short cut and cost effective strategy for
drugs development. Happy reading;
Dear
Dr. Othman
Your
article on Diabetes was very interesting especially the aspect of “Reverse
pharmacology”. I wish to comment on this subject for clarity to the general
public while hopping that the relevant stakeholders will beam their searchlight
for cost effective way to drugs development. Reverse pharmacology known as “target
base drug discovery” is a trans discipline that is comprised of three phases:
·
Experiential phase: includes robust documentation
of clinical observations of the biodynamic effects of standardized Ayurvedic
drugs by meticulous record keeping.
·
Exploratory studies: for tolerability,
drug-interactions, dose-range finding in ambulant patients of defined subsets
of the disease and para-clinical studies in relevant in vitro and in vivo
models to evaluate the target-activity.
·
Experimental studies: basic and clinical, at several
levels of biological organization, to identify and validate the reverse
pharmacological correlates of Ayurvedic drug safety and efficacy.
In lay-terms reverse pharmacology
involves a hypothesis based on available data that a particular molecule is
safe and can modulate the functions of a given protein complex in the body to
yield a particular effect. This is then followed by identifying which plants
may likely contain such molecules.
In this process the safety
remains the most important starting point and the efficacy is a matter of later
validation. This method of drug discovery was first started in India and has
gained much popularity and is widely used in drug discovery these days instead
of the classical/conventional method of drug discovery.
Drug discovery in Ayurveda
follows a reverse pharmacology pathway. The ayurvedic knowledge database
provides drug-researchers with information to start from a well-tested and safe
botanical material. Thus, clinical experiences, observations or available data
becomes a starting point whereas in conventional drug research, it comes at the
end. Reverse pharmacology provides three basic advantages when compared with
conventional pharmacology. It is less time consuming, it is more cost-effective
and participants suffer less toxicity. Most of the compounds used are part of
routinely used traditional medicines and hence their
tolerance and safety are relatively well known. Examples of compounds that have
come out of Ayurvedic experiential base include Rauwolfia alkaloids for hypertension, Guggulsterons as
hypolipidemic agents, phyllanthis as
antivirals.
Reverse pharmacology is a way out
for the developing country like Nigeria because of rising cost of drug
development using conventional method. Today, the drug development industry is
really facing major challenges in sustainability and growth. The average cost
of discovering, developing and launching a new drug in June 2008 was
inordinately high and represented a dramatic increase over the average cost
from 1995. Research and development expenses have risen from $2 billion in 1980
to over $40 billion in 2007. Drug discovery and development process involves a
10-15 years of investigation period and investments of the order of US $ 1 to
1.5 billion. This extremely complex, technology based and capital-intensive
process has resulted in ‘target rich lead poor’ performance. Pharmaceutical
companies have to look beyond conventional drug discovery and development
approaches not only to expedite the process, but also to ensure that safer and
effective drugs could be launched faster and sustained. Natural product drug
discovery, ethno-pharmacology, traditional, complementary and alternative
medicines are re-emerging as new strategic options. The World Health
Organization’s commission on intellectual property and innovation in public
health has duly recognized the promise and role of traditional medicine in drug
development for affordable health solutions.
The discovery of Artemisinin for malaria is a result of
scientific work based knowledge from traditional Chinese medicine and
represents an excellent case for reverse pharmacology approach. The herb Artemisia annua has been used for many
centuries in Chinese traditional medicine as a treatment for fever and malaria.
In 1971, Chinese chemists isolated the active substance Artemisinin from the leafy portions of the plant responsible for
its reputed medicinal action. This product has now undergone several trials and
it was subsequently launched alongside its derivatives as a totally new class
of anti-malarial.
Another example is the drug
candidate Desoris. It is a herbal
beneficiated extract of a single plant that has a novel mechanism of action and
effectively modulates cellular function in the treatment of psoriasis. Lupin
laboratories in India commenced phase 1 clinical trial in September 2004 and
successfully completed it. The drug was subsequently developed conforming to
the US FDA guidelines for botanicals and DCGI norms on new drug development.
The entire process too, about 5-6 years to complete and cost US $ 5 million
compared to the conventional classical pharmacology path which would have taken
10-15 years and up to US $ 1-1.5 billion to complete.
Despite the vast potential and
possibilities only very few success stories of reverse pharmacology are
available presently. Most of the work done in this field has remained within
clinics of traditional practitioners or confined to academic research
laboratories and not taken by major multinational companies skilled in research
and development. Drug discoveries from reverse pharmacology will be practically
impossible without the scientific or technical contributions from the
pharmaceutical companies. The pharmaceutical industry needs many more successes
like Artemisinin. The public and
private sectors can partner with the academia and industry to harness the
potentials of this seemingly unfashionable but extremely rich explorations
based on traditional knowledge.
Many countries are becoming
increasingly aware of the value of their traditional knowledge. Global
pharmaceutical industry is looking for innovative solutions to their existing
impasse on innovation deficit to re-activate and re-energize discovery
pipeline. Therefore, innovative approaches inspired by traditional knowledge
will remain important to fast forward the discovery process and add new life
especially in the existing global economic environment. Traditional knowledge
and experiential database can provide new functional leads to reduce time,
money and toxicity- the three main challenges in drug development. These
records are particularly valuable since these compounds have been tested for
thousands of years on people. Reverse pharmacology approaches need to be
developed further and optimized as novel means for fast track drug discovery
and development of newer, safer and effective drugs. I therefore congratulate
Dr. Muhammad Auwal Ibrahim for his work on the diabetes using African herbs and
called on the stakeholders and relevant government agencies to support his
invention to logical conclusion.
Dear Dr. Othman,
I have been an ardent reader of your column and I must
confess the very wide variety of breakthroughs reported and their sources
marvel me. You are surely doing a good search. I want to use this medium to
commend the
initiative and encourage you to continue the good effort which has two clear
benefits- first, it informs and sensitizes potential users of the technology
breakthrough to know what and where it is available and secondly, for
researchers and others engaged in similar endeavours to know others engaged in
activities related to theirs and their level of achievements for possible
collaboration and information exchange for national development. Please,
keep it up.
Dear Dr. M. K. Othman
Your article on Diabetes is very interesting. I
believe it is a way forward for patients with diabetes. However, even before
this research, many people in the rural areas cure diabetes with local herbs,
example herbs like Yadia, raidore (in hausa
language) etc. Now that the Chinese
people have come up with this Technology “Reverse pharmacology, and all they
need is just to know if it's not dangerous to the health thereby reducing 15 years
of research work to only 2 years is really very interesting and impressive. But
what is the next step after Dr Auwal’s research work? It is hoped that the
relevant government agencies will support the final development of this drug
and make it available at an affordable price with easy access. This is because
diabetes is a disease that affects many Nigerians today without known permanent
cure
Your article on Diabtes was
particularly very interesting especially the reverse pharmacology. I wish
called on the Pharmacists to take advantage of this technology to address the
various ailments suffering many Nigerians. They should work hand in hand with
traditional medicine practitioners to discover herbs that can be used to cure
many diseases in our society using reverse pharmacology
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