Chinese scientists have launched a herbal medicine gene database project this month which is expected to combine traditional Chinese medical science with gene pharmaceutical technology. Chen Zhu, director of the China Human Genome Center at Shanghai said at the ongoing 2002 International Human Genome Meeting that gene technology would be used to decode the mysterious effect of traditional Chinese medicine. The project, named "the world''s largest native compound gene database", will detect more than 5,000 effective elements of traditional Chinese medicine and put them into the herbal medicine gene database."
For thousands of years, the Chinese have used mixtures of plant and animal bones to cure disease with a success rate that continues to baffle modern science. After the native compound gene database is established, Chinese scientists will use all the 5,000 effective elements discovered in traditional Chinese medicine to test disease-related human genes, in a bid to decipher traditional Chinese medicine.
PLD technique makes more convenient drug delivery
While there are several asthma drugs -- known as glucocorticoids -- on the market, they can have serious side effects, including inhibiting growth in children, hypertension, and suppression of the immune system. The surprising part of all this is that the side effects do not result from the action of the drugs on the lung, but rather from their absorption through the lung tissue into the blood stream. However, with the success of a new coating (in rats, human trials will follow), this situation may change. The coating was developed by a team of researchers at University of Florida''s pharmacy and engineering departments and covers tiny drug particles contained in many asthma inhalers with a polymer about 1000 times thinner than a human hair.
The coated drugs need several hours to dissolve, reducing the need for frequent inhaler use and minimizing unintended, potentially harmful, release of the drugs into the blood stream. So patients will not bear the headache of using the inhaler as many times as before (patient noncompliance or improper compliance is always a major issue), and moreover no systemic effects were observed A technique called pulsed laser deposition (PLD)--generally used to fabricate extremely thin coatings on flat surfaces in semiconductor processing--was utilized to help overcome the challenges. With slight modifications to the technique, the researchers were able project at high velocity, a biodegradable polymer with a very high-energy laser beam into a chamber containing suspended drug particles. While the polymer-coated drugs have shown good performance in cell cultures as well as in testing in rats, the polymer coating will still require extensive testing in humans before FDA approval can be granted.. It is likely that the coating will be benign, and the coated drugs would be marketable within the next 5-10 years..
Marketed and developmental products for ED
Early products for treating erectile dysfunction (ED )included penile implants and suction devices and were followed by injectable pharmaceutical products containing drugs like phentolamine and alprostadil etc. The market for ED has grown dramatically with the introduction of Viagra (sildenafil), an oral drug from Pfizer in April 1998. and worldwide sales reached $1 billion in 1999, setting a record for the fastest growth of any new drug Viagra, a PDE (phosphodiesterase) 5 inhibitor, works by relaxing the smooth muscles in the penis, allowing blood to flow in to achieve and maintain an erection. Despite its success, Viagra has some side effects.
Several companies are therefore developing oral drugs with better efficacy, Bayer is in Phase III trials of Nuviva (vardenafil), a PDE 5 inhibitor . The drug could reach the market by the end of 2002. Nastech is testing intranasal delivery of apomorphine in a pilot Phase II. Phase. ICOS, in collaboration with Eli Lilly, is developing Cialis,( IC351), a PDE 5 inhibitor. The drug took effect in 30 minutes and the men had the ability to achieve erections for up to 24 hours. The US FDA approval is anticipated in the latter half of 2002. Clinical trials of two oral drugs for ED have been discontinued. (phentolamine, and sublingual apomorphine) . Topiglan, a topical gel of prostaglandin E1 is in phase III trial, Alprox-TD (alprostadil )is effective within 15-20 minutes after application. International Medical Innovations has developed a cream formulation containing the vasodilator, nitroglycerin. Several natural products are marketed as aphrodisiacs to increase sexual drive and performance such as Viramax, an herbal mixture; VasoRect containing L-arginine as its main ingredient and Vigorex, which is derived from oats. These products are in the class of dietary supplements and lack clinical proof of efficacy.
Compiled from WWW by Dr. Venkat Appaji Padmanabhunie-mail : appajipv@hotmail.com