Toxicology

Toxicology

Drug therapy is an important aspect of the modern healthcare. Nevertheless, exposure to some drugs in a certain manner and over certain periods of time has been proven to have effects on the user. They are one of the major causes of deaths in advanced countries. According to recent studies, a drug derived from iridium metal has potential to effectively treat cancer. However, iridium is the same metal which most scientists believe to be one of the reasons for the extinction of dinosaurs. As such, thorough tests on the metal are crucial to ensure it does not pose more harm than good to the humans it is administered to. Various models such as animal, cell cultures or computer simulation could be used to test the drug’s safety and effectiveness in treating cancer. However, cell culture is the most suitable model for this task. Efficacy, toxicity, and lethality are important tests used to determine whether anti-cancer drugs and generally any other drug is suitable for use in drug therapy.

Cell culture is a technique used to grow and maintain cells or tissues outside their natural environment under the conditions essential for their survival. The cells/tissues are derived from living things and preserved in laboratories. Cell culture has been a fundamental basis for many studies including in-vitro drugs assays (Kolesnikova & Moiseeva, 2017). The model has been effective in testing the safety and effectiveness of chemotherapy before. The model bears advantages and disadvantages in its use. It is economical especially for the large-scale production of drugs since cell culture production is cheaper than the use of live animals in testing. The cells and tissues used are closely monitored enabling accuracy and reliability of the outcome of the tests. The model also enables one to concentrate on specific cells contributing to more effective and detailed results. The screening is relatively faster and negative in-vitro equals negative in-vivo. However, the growth of certain hybridomas is inhibited in cell culture. Proper glycosylation may also be lost in cell culture reducing binding affinity and increasing immunogenicity (Mucke, 2015).

Lack of clinical efficacy and toxicity are the main reasons why most substances containing medicinal elements are not approved for drug therapy. Efficacy tests and toxicity tests must be carried out before a drug is approved for medical use. Lethality tests are also essential in drug testing and development although not as important as efficacy and toxicity tests. In determining whether the experimental drug derived from the metal iridium is suitable for approval of use on human beings, more than one test is needed to ensure certainty.

Efficacy test is simply a test used to determine the capacity of a drug to bring about beneficial change to the body. Together with therapeutic index, the test is used to determine the dosage that will provide the amount of chemical needed to render a safe treatment (Nuermberger, 2017). The median efficacy dosage (ED50) is the safe and efficient dosage of a drug. The therapeutic index indicates the length of the margin between lethal/toxic dose and effective dose. As such, the higher the therapeutic margin (TI) the better. Patient-oriented outcomes such as improved function, prolonged, and relief of symptoms are some of the outcomes used to determine efficacy and effectiveness of a drug.

Toxicity testing is used to assess the probable health risks of exposure to the drug. The main objective of the test is to determine whether any adverse effect may occur as a result of using the drug in medical therapy. Scientists commonly use in-vivo and in-vitro methods to perform the test. However, data on human exposure to the drugs are sometimes used in toxicity testing. The major toxicity tests carried out include; neurotoxicity, drug-induced liver injury, the toxicity of the genes, immunogenicity, the toxicity of the renal system, general toxicity among others (Hera BioLabs, 2016). For a toxicity test to be effective it must involve a biological model, a measurable endpoint, and well-developed protocol. Some of the endpoints looked out for in the test includes inflammation, peroxidation of lipids, immune-suppression, necrosis and receptor interaction.

Lethality testing is used to determine the dosage that can be fatal to a species. It is a form of acute toxicity testing with death as the only endpoint of the test. The test determines the median lethal dosage (LD50) of a drug. Since the animal or the cells used for the test dies, the test cannot be used to provide information on chronic effects of the substance on a human body (Animal Ethics Infolink, 2017). The test has been criticized to be wastage of resources since death is the least desirable measure of toxicity. However, the information obtained from lethality testing is important in labeling and regulatory purposes of the drug.

From the tests, important information that will help determine whether the drug derived from iridium metal would be suitable for cancer treatment will be gathered. This information will bear in it the dosage that will be effective yet safe for use in a human body and the length and type of exposure through which the drug may lead to toxicity. The test can also help to tell the amount through which when the drug is exceeded can be fatal to caution the users. The same protocol should be used to test drugs before approving them for usage. Although a different model of testing could be used, efficacy and toxicity tests should always be undertaken in products such as drugs, cosmetics, and herbal medicines.

In conclusion, cancer is one of the world’s leading causes of mortality.  Finding an effective treatment for the diseases could save many lives. However, there is more to approving a drug for use than its possession of treating capabilities. As discussed, there are various models of testing drugs. The most popular ones are animal testing, computer simulation, and cell cultures. With animal testing being perceived by many as unethical, cell culture seems to stand out among the models as computer simulation has not been able to completely mimic the human system. Efficacy tests and toxicity tests are crucial in determining whether a proposed drug is suitable for use.