These times are smart times. And now we have ‘smart drugs’ that deliver themselves to the correct path of the body, at the correct time and in correct amount.
Worldwide research now ensures that drugs introduced in the body take the smartest scientific path rather than nature’s haphazard course. In, India, researchers at the Indian institute of Technology (IIT), Mumbai, the Central Drug Research Institute (CDRI),Lucknow, and the National Chemical Laboratory(NCL),Pune, have long been on the path of smart drug delivery systems. Photo chemist Anil Kumar singh of IIT, Mumbai , has already turned in –vitro results of smart drugs for the treatment of tumuors. Traditional chemotherapy is much like carpet bombing, leading to destruction of not only the cancer cells, but also other cells. But Singh’s smart drug delivery system works like a smart bomb. Here a drug is encapsulated in an inactive molecule, taken to the diseased site in the body, and only then activated- in Singh’s case, with light.
“There have many smart delivery systems for ‘caging’ drugs developed world wide. But most use ultra-violet light which is harmful”, says singh. ”In our case, the activating light is regular, visible light, which isn’t harmful.
The smart drug delivery system also includes a sustained delivery where same effect can be achieved with low dosage. “ Smart drugs can also ‘sense and deliver’” says jayesh Belare, head of the Bioschool, IIT, Mumbai. The school is working on the nanoparticle-based smart drug delivery system. “ For instance, in the case of insulin, it can sense the level of blood sugar and release only the amount that’s is actually needed, instead of a standard, flat amount. If only half a tablet is needed, it delivers half, not the entire tablet”.
Leading pharmaceutical companies are investing in the smart drug delivery system, encouraged by the fact that it’s a low cost research area compared to developing new drugs, and pays off in a shorter time. The global smart drug delivery market, estimated at around $40 billion in 2000, is expected to grow to $70 billion by 2005. In India, Ranbaxy, Wockhardt,Lupen, Valois India have commissioned research in smart drugs.
According to Jag Mohan Khanna, R&D head of Ranbaxy, Gurgoan, the smart drug delivery system has been growing research area since the last three or four decades. The use of the skin patch for motion sickness and hormone replacement therapy are examples of existing, though the older, smart delivery systems says Bellare, ”Traditional systems of medicine, like ayurveda, can help the cause of smarty drugs too. For instance, ‘bhasma’, an ayurvedic ingredient, contains nanoparticles, and can be used in smart drugs. So often it’s a question of looking traditional systems with a modern viewpoint.
Three years ago, a team of scientists from Rutgers, the University of Medicine and dentistry, Newjersey and Cancer institute of New Jersey added a new twist to the smart drug carrier that not only seeks out targeted diseased cells in the body, but also functions as tiny gel ‘medicine cabinet’ within the body. “When injected under the skin, the gel l drug carrier forms a tiny lump that serves as medicine cabinet, administrating the drug to the patient daily, weekly or monthly basis, as needed,” explains Patrick Sinko, chairman of the department of pharmaceutics, Rutgers’s College of pharmacy.” It’s ideal for elderly patient’s or schizophrenics who forget to take their medicine”.
According to Bellare, a ‘medicine cabinet’ of sorts is already used to administer drugs for pregnancy –induced hypertension.” The real challenge be if a similar ‘cabinet’ can be developed for administering insulin to patients on a sustained basis”, he says. “But then, the smart drug scene has plenty of potential and world research is yet to tap it fully. The best work in this area is still to come.”
SMART DRUG OPTIONS
? SMART PILLS | Pills that can withstand the acids of the stomach and slowly deliver the drug where needed. There’s also the smart chip that can be programmed to release a single or multiple drugs continuously or in pulses.
? INHALATION | In pulmonary delivery, the particle for inhalation flies deep in to the alveolar region, giving it good positioning for controlled drug release.
? PAINLESS INJECTION | Injection is usually avoided because of pain, but it’s effective as it bypasses many of the body defenses. Now technology has made injection painless. For instance, the ‘Mosquito’, a device that’s a small disc with a needle that pierces only seven micrometers into the skin, which is above nerve endings.
? ULTRASOUND | Ultrasound makes dermal absorption easier. Placing a small ultra sound device against the skin for 15 seconds makes it more permeable, allowing larger molecules to enter the blood stream.