As humanity continues its onslaught of attacks against the various diseases that have debilitated countless for millennia, the stockpile of the weaponry we use is constantly evolving. For thousands of years, people depended mainly on plant extracts for curing their maladies. Then came the age of man-made compounds. Today, we stand at a precipice where the man-made therapies are designed to harness or hijack the disease producing pathways or to mimic internal body response to disease.
For patients suffering from Multiple Sclerosis (MS), a spectrum of neurodegenerative disorders, where one’s own immune system attacks the nervous system, treatment options are few. One of the first line of treatments prescribed for the relapsing form of MS is interferon therapy.
Just as a person might call 911 after realising the presence of an intruder in their house, cells in our body produce proteins called interferons when confronted by a virus, bacteria, tumor or other pathogens attacking it. This 911 call by the cells activates the immune system, our internal cops, to defend the body. Interferon therapy relies on introducing these molecules within the patients body to mimic alarm signals and preempt progression of disease, in addition to relieving the symptoms.
As currently used, interferon therapy has certain drawbacks. Betaseron, a commercially available brand for MS drug is administered as injections on a weekly basis. Not only do these shots cause physical discomfort, but also there are possible complications ranging from flu-like symptoms to inflammation and above all the psychological handicap of being dependent on frequent medications.
Any molecule introduced into the body is subjected to degradation and removal. Proteins like interferons are broken down and rendered ineffective by the proteolytic enzymes (that break proteins) within the blood. Then there is removal of molecules by the kidneys as they try to purify the blood of anything foreign. These processes affect the stability of the drugs and thus the need of frequent medication.The goal of any therapy is to raise the quality of life of the patients and there is constant research to achieve the same for patients of MS.
As a way to circumvent this for MS patients, scientists are employing a strategy used erstwhile mainly for cancer and Hepatitis B and C medication. Administration of therapeutic biomolecules chemically attached to polymers called polyethylene glycol (PEG), a compound that is not detected by the body as foreign, the frequency of drug administration has been reduced without compromising on its efficacy or safety.
This strategy, called PEGlyation, is currently being employed to the Interferor beta-1a that is used as a first line of defense for patients with relapsing MS. And the results seem very promising. Studies in both mice and Rhesus monkeys, with whom we share about 99% and 99.9% of our DNA, have shown that the PEG-linked Interferon is not any more toxic than the conventional Interferon, but is rather more stable, and is retained in the body for a longer time.
In the heels of these results, currently a two-year Phase III Clinical Trail is underway to test the efficacy and suitability of PEG-linked Interferon beta-1a , for use in human patients.
Being conducted simultaneously across five countries, this trial carries the promise of further improving the quality of life of the patients.
Let’s have our fingers crossed.