How to reduce the toxicity of chemotherapy and to increase the body's defence response to it
Individual pharmacotherapy specializes in the pharmacotherapeutic monitoring of oncological drugs, which provides for the determination of measures and the interpretation of indicators of the concentration of drugs in the blood in order to determine the effective and least toxic dosage of the drug for each patient.
Errors in the selection of cancer treatment
Traditionally, chemotherapy uses certain doses of drugs that are set in accordance with parameters such as the surface of the body. However, each patient is unique, and for one out of every two patients this form of dosage determination is not optimal.
So, it was found that about 30-40% of patients who used this form to treat received insufficient doses for them, while 15-20% of patients received excessive ones. This is due to variability relating to the processes of absorption, distribution, metabolism and excretion of the drug by each patient, which leads to variability in systemic perception and, finally, in the observed therapeutic and / or toxic effect.
In this regard, individual medicine in oncology should be something more than just issuing a properly selected drug to a specific patient. One should take a step forward and control that the received dose of the drug ensures its correct perception.
What does the individual pharmacotherapy
The introduction of individual pharmacotherapy has demonstrated, both in the treatment of solid tumors and hematologic tumors, an increase in reaction rates, both in time to progression and in overall survival and reduction of toxicity.
In addition, it is an added value when making clinical decisions in situations such as those listed below:
- Warns treatment errors associated with failure to achieve proper systemic exposure
- Lets to recommend a dose increase in safe form
- Distinguishes between good tolerability of treatment and insufficiency of received doses
- In cases of toxicity after chemotherapy, it determines which drug causes the indicated toxicity and makes it possible to reduce the dosage of only the therapeutic agent that causes it, without affecting the effectiveness of the other drugs
- Detects treatment resistance deficiencies (in cases of oral medication)
- Defines the interaction of "drug-drug" and "drug-food product"
Dr. Vanessa Escudero, a physician at the pharmacy at Quironsalud’s Department of Individual Pharmacotherapy, is convinced that “the future of the fight against cancer is linked to the individualization of treatment. To do this, it is necessary to know not only the effect that chemotherapy has on the tumor, but also the effect that the human body has on the chemotherapy used.
Thus, conventional chemotherapy dosage regimens are currently based on indicators such as weight and height. However, the behavior of the drug inside each patient can vary from toxicity to inefficiency.
In the face of the reality of treatment activities widely described in biomedical literature, the real challenge is to determine, as soon as possible, which patients will not achieve the desired response to treatment and which patients may develop adverse reactions that limit the possibilities of pharmacological treatment. This is key to obtaining the desired results and reducing the fear that patients experience when using chemotherapy treatments, and to achieve these two goals is to improve the patient’s quality of life."
Antitumor treatment optimization procedure
The procedure used to optimize antitumor treatment followed in the individual pharmacotherapy department is relatively simple.
After the patient receives the first dose of chemotherapy, blood tests are taken to determine the amount of the drug in the blood and the magnitude of the reaction (therapeutic or toxic) in the patient. The level of drugs in the blood is determined using high-performance liquid chromatography systems, fluorometric and / or ultraviolet radiation detectors, ICP or ELISA optical emission spectrometry.
On the other hand, the magnitude of the reaction (therapeutic or toxic) in a patient is determined both by using objective measurements of various blood parameters and by using medical examinations conducted by the medical staff of the center.
These data together allow us to determine the characteristics inherent in a particular patient, in conjunction with the prescribed treatment. Thus, it becomes possible to establish how the absorption and distribution of the drug in a particular patient occurs and how it is excreted from the body; what is the sensitivity of the patient in relation to the development of adverse reactions and what is his individual response to this particular tumor.
This information allows you to assign the optimal dose, which increases the possibility of achieving the desired reaction and reduces the risk of adverse reactions.
One of the most advanced and well-known departments of individual pharmacotherapy in the world is located in Quironsalud, the largest group of hospitals in Spain, which has the award "For the best ideas in medicine". Currently, in it more than 25 anti-neoplastic agents are monitored and the list of services provided is increased annually in order to achieve a potential 100% monitoring.