DNA REPURPOSING

Source: TechnologyNetwork

Disclaimer: Copyright infringement not intended.

Context

A group has shown that Selegiline (L-deprenyl), an antidepressantdrug from a class of drugs called monoamine oxidase (MAO) inhibitors, might be applied as anticancer therapeutics for breast cancer.

Details

Background

• An antidepressant drug has the potential of being repurposed to provide cost effective solution for treatment of breast cancer.
• Due to expensive costs, long development times, and the requirement for drug trials and regulatory approvals, generating new and effective anticancer medications has been complex.
• However, biomedical scientists today frequently use medication repurposing for drug discovery.

What is Drug Repurposing?

• Drug repurposing, also known as drug repositioning or drug reprofiling, involves the study of new therapeutic indications for drugs already approved or under investigation.
• This approach is remarkably valued in the building of entirely new drugs in cases where:

the process is too costly or time-consuming or when rapid solutions are imperative during specific health emergencies, such as the COVID-19 pandemic.

Key Drug Repurposing Approaches

• Drug-centric approach: It covers the expansion of indications of an already approved or investigational drug to new medical conditions, including off-label use, abandoned drugs, or drugs at the end of their patent exclusivity period.
• Disease-centric approach: It involves matching diseases with few or no treatments to compounds that have a therapeutic effect on similar biological mechanisms that help in treating rare diseases.
• Target-centric approach: This includes matching a new medical condition with a known drug that modulates specific molecular targets associated with the disease.

Advantages of Drug Repurposing

• Faster and less expensive drug approval: Drug discovery traditionally takes 10-15 years and costs up to $2.6 billion. Drug repurposing significantly reduces this timeline to 3-12 years and cuts costs by 50-60%
• Higher success rate: About 30% of repurposed drugs succeed in reaching the market whereas approximately 10% for new drugs happen to be successful.
• Treatments for rare diseases: Repurposing offers a hope for many rare diseases without current treatments.
• Increased ROI for Pharmaceutical Companies: Repurposing extends the revenue potential of existing portfolio drugs, mitigating the effects of patent expiry, and providing new market opportunities for existing assets.
• Rapid Response to Health Emergencies: Drug repurposing allows for a quicker response to emergent health crises. During the COVID-19 pandemic, drugs like Remdesivir and Dexamethasone were repurposed to address urgent treatment needs.
• Reduced Need for Animal Testing: Since the pharmacokinetics and pharmacodynamics of repurposed drugs are already well understood, preclinical animal testing can be bypassed, saving time and resources.

Challenges

Technical Issues to Overcome

• Volume of Data.
• Drug repositioning involves various data types from different sources, such as biology, chemistry, and omics. The diversity of the data in turn creates a problem in integrating and analyzing information.
• Processes for data analysis require scalable computing platforms.
• In the absence of expertise across domains, an organization may not be able to develop advanced models such as knowledge graphs or neural networks.

Efficacy and Safety

• Repurposed drugs may not be as effective for new indications as they were for the original ones.
• While repurposed drugs have known safety profiles, trials on safety may still be necessary for the new indication, reducing the cost-saving advantage.

IP and Timing

• IP Barriers: Securing patents for repurposed drugs can be complex, and companies need to evaluate commercial viability. If patents expire during repurposing, exclusivity is lost.
• Timing: Patent extension through new indications must occur before the original patent expires. If exclusivity is lost, drug repurposing efforts may no longer be commercially viable.

Sources:PIB 

PRACTICE QUESTION Q: What do you understand by the concept of Drug Repurposing? Discuss its significance in modern medicine, particularly in the context of the COVID-19 pandemic. Also, analyze the challenges associated with drug repurposing techniques. (250 words)