What is Monoclonal Antibody Therapy?

Since the early description of monoclonal antibodies by Kohler and Milstein in 1975 there has been considerable interest in their adoption for human sero therapy.

In 1895 Hericourt and Richet described the first trials in which cancer cells were injected into animals to raise an antiserum for treating the patient. Their results seemed very promising and several patients with different types of advanced cancer are treated, each receiving an individual, tailor-made antiserum.

None of them was cured, but they showed significant improvements in their symptoms. It was discovered that an antiserum contains a mixture of many different antibodies, each one directed against a different antigens on cancer cells.

Many of these antigens are also present on normal tissue cells and so the antibodies against them could be harmful. Hybridoma technique developed by Georges Kohler Cesar Milstein and Niels Kaj Jerne for the production of monoclonal antibodies allowed their development in the mid 1970s.

Chimeric, humanised and fully humanised mAb can now be made by recombinant engineering.

Specificity against antigen made monoclonal antibodies (mAbs) made them blockbuster potential drugs.

The specificity of monoclonal antibodies has tremendous clinical value and makes them very attractive therapeutics. The focus, which was once dominated by their use in oncology, has now broadened to encompass additional disease areas.

About a quarter of all biotech drugs in development are mAb, and around 30 products are in use or being investigated. Licensed products are available for inhibition of alloimmune and autoimmune reactivity, and for antitumour, antiplatelet, or antiviral therapy.

Monoclonal antibodies are now a major component of the pharmaceutical pipeline. Of the estimated 370 biotechnology-based drugs in development in 2000, approximately 70 are mAbs, second only to therapeutic vaccines. There are currently 132 mAb products in development.

Majority of the products are either humanized (42%) mAbs or fully human (28%) mAbs. A healthy future is anticipated for novel mAbs based therapies.

Certain monoclonal antibodies have been introduced into human medicine for controlling various problems are as follows:

To suppress the immune system:

Muromonab-CD3 (OKT3) and two humanized anti-CD3 monoclonals are used in transplantation treatments to prevent acute rejection of organ.

Infliximab is useful in controlling certain inflammatory diseases such as rheumatoid arthritis.

Omalizumab showed positive effects against allergic asthma by preventing IgE’s attachment to mast cells. Daclizumab is useful to prevent acute rejection of transplanted kidneys.

To kill or inhibit malignant cells

Rituximab is used to treat B-cell lymphomas.

Trastuzumab is the only monoclonal so far that seems to be effective against solid tumors.

Angiogenesis Inhibitors

Vitaxin. Bevacizumab has shown some promise in shrinking solid tumors without harmful side effects by inhibiting angiogenesis.

Abciximab is helpful in preventing reclogging of the coronary arteries in patients who have undergone angioplasty.