Re-Purposing Old Drugs to Treat New Diseases
Recycling is environmentally friendly, from recycling Christmas packaging to paper bags, we're all conscious of our responsibility towards the environment. But how about the numerous drugs stuck in development limbo? Drugs that weren't approved for a particular disease or simply too ineffective for the condition or disease they were meant to cure, drugs that were replaced by newer more efficient drugs, business reasons, etc. The reasons for many prescription drugs to fall into disuse are many. But now the FDA is working with pharmacological companies to repurpose & rescue drugs that were previously developed to treat other diseases & illnesses.
Developing a brand new drug from scratch costs plenty of money & can take over 10 years from initial research to pharmacological trails, therapeutic development processes & more. The emergence of rarer diseases & the advances in medical sciences in identifying previously unknown illnesses & genetic conditions means that it's vital to reduce the time taken to develop a drug & introduce it to therapeutic use, bringing down costs, & helping more patients.
Drug "rescue" refers to small molecules and biologics that were previously researched but not developed & submitted to the FDA. Drug repurposing or repositioning as its sometimes termed refers to small molecules or biologic already approved by FDA, except this time they're being researched to see if they will be effective & safe in treating other diseases.
Many of these rescued or re- positioned molecules have already undergone medical trials & were tested in humans. Because data on pharmacology, formulation and probable toxicity for these drugs are already available, it's expected that they could get sent for review by the FDA much faster. If they're approved these repurposed or rescued drugs could get into the main healthcare stream much faster than new drugs.
Aris Persidis, president and co-founder of biotechnology company Biovista, says, "It is a very easy way to explore whether something that is therapeutically beneficial in one area and for one type of patient might be useful for another type of patient."
The case of Mifepristone or RU-38486 is a classic example. Developed in the mid- 1980s as an artificial steroid capable of blocking the glucocorticoid receptor to treat Cushing's syndrome, researchers found that the molecule terminated pregnancies in gestating animals. Thus this drug was investigated extensively as a birth control pill targeting early pregnancies, and it was only in early 2012 that the FDA approved mifepristone or RU-38486 to control hyperglycemia in adults with endogenous Cushing's syndrome. Though, FDA had approved mifepristone to terminate early stage pregnancies 10 years earlier.
Another "poster-child" as it is dubbed, is the baby defects drug Thalidomide. Prescribed as a morning sickness drug, Thalidomide caused birth defects in babies born during the 1950s; many babies were born with limbs that looked like seal flippers. It's now used to combat a rare type of cancer, multiple myeloma, though the cancer eventually returns. Researchers at the Dana-Farber Cancer Institute, New York, discovered that Thalidomide worked differently on the myeloma cells & killed them, along with learning why the drug stopped working against cancer cells. Thalidomide & its compounds are proving to be more versatile than scientists imagined. William Kaelin, the lead researcher of Thalidomide says, "A number of other cancer proteins that we think of as being undruggable might be attacked. I am most excited about the possibility of better thalidomides and other drugs that basically borrow from the thalidomide paradigm".
These older drugs give hope to many researchers & physicians who hope to discover new cures in previously forgotten drugs. With probably thousands of drugs waiting to be re-discovered & repurposed, exciting new therapies are now possible for previously untreatable diseases.