Familiarity with transplant rejection drugs

Anti-transplant drugs or immunosuppressive drugs are one of the most important reasons for the success of organ transplants today.

At the beginning of organ transplantation in the 1950s, the success rate of transplantation was very low due to the prevalence of transplant rejection. The prevalence of transplant rejection was about 80% and the success rate of transplantation was less than 40%. As a result, few centers were transplanted. Medical articles related to organ transplants at that time are full of reports that a transplant member became disabled a few days or weeks after becoming active.

At the beginning of organ transplantation, there were only a few anti-transplant drugs that, due to their low efficacy, made the development of transplant science a serious problem.

With the advent of cyclosporine on the market in the 1970s, the success rate of transplants has greatly increased.

It should be noted that anti-transplant drugs nonspecificly reduce the level of activity of the immune system, so these drugs are also associated with side effects.

Because each of these drugs only partially inhibits the immune system activation mechanisms, it is sometimes necessary for the patient to take several drugs.

Our body’s immune system is designed to first introduce a group of immune cells to the rest of the immune system when exposed to foreign tissue. This leads to the activation of the immune system at various levels, including the activation of immune cells, the production and secretion of antibodies, and so on.

To protect our body, the immune system has several mechanisms for activation, so to weaken this system, we must inhibit these multiple activation mechanisms. As a result, the patient usually takes several medications.

New anti-graft drugs inhibit one or more mechanisms of immune activation. This inhibition is not specific to the activation of the immune system against the transplanted organ, so as the level of activity of the immune system decreases, risks such as infections increase.

On the other hand, some cancers are also associated with viruses, so the prevalence of cancers, especially cancer-related cancers, is high in transplant patients who have taken these drugs for a long time.

Other common side effects of these drugs include high blood pressure, diabetes, and hyperlipidemia, all of which are risk factors for cardiovascular disease. Therefore, cardiovascular disease or its exacerbation is very common in transplant patients.

Corticosteroids are one of the most commonly used drugs in transplant patients. Common side effects of corticosteroids include physical changes such as obesity, diabetes, and osteoporosis.

Because the risk of rejection is reduced after the first year of transplantation, it is necessary for the transplant team to reduce the amount of these drugs slightly after the first year so that the patient does not have side effects. Of course, any reduction in the amount of drug also carries the risk of transplant rejection.

Therefore, the transplant team must carefully monitor the patient. Unfortunately, there is still no scientific method for assessing the level of activity of the immune system, so the line between the risk of transplant rejection and the risk of complications is very narrow. The skill of the transplant team is very important in this regard and it is necessary for the doctors of the transplant team to carefully monitor the patient’s condition.

Dr. Reza Saidi Firoozabadi – Transplant surgeon