Consider the last time you took medication, such as a pain reliever or a cough syrup. While you were taking the drug, what thoughts did you have in your mind? You probably didn’t give much thought to the drug’s origins, although scientists and physicians may have spent a lot of time working on it.
Getting a medication to your local pharmacy is a difficult, time-consuming, and sometimes costly process. The study, development, and manufacture of molecules to cure illness has become a complex economic model for pharmaceutical corporations. Laboratory experiments are used to find and enhance the medicine, while clinical trials are used to assess the drug’s safety and effectiveness for patients.
In spite of scientific advancements, new drugs are being authorized less often.
There is a lack of man-made molecules to fill the void left by the discovery of naturally occurring molecules (natural products) found in sources including plants, bacteria, and fungal organisms. Medical research has a major problem in meeting the growing need for novel medicines.
Phase One: Drug Discovery
The development of new medicines depends on the efforts of chemists, biologists, and doctors. While chemists work on chemicals that might one day become medications, biologists focus on the molecules that cause illness. Drug targets include huge macromolecules (such as proteins) or cancer cells, and researchers then look for compounds that disrupt the protein or destroy the malignant cell as a whole. The capacity of chemistry to comprehend molecular interactions is critical in the development of medications that treat illness.
The quest for a drug’s molecular key is akin to that of unlocking a disease’s lock. The structure of the key and lock, as well as the way various keys interact with the lock, are among the many questions that scientists are attempting to answer. The molecular key must be complementary in its geometric form and interactions with a cavity in the biomolecule in order to fit well and inhibit the function of the pharmacological target. Keys and locks may be tested against each other, but this is difficult since there are so many of each. There may not be a lock for every condition, and one key may suit numerous locks, further complicating things.
Drug Discovery: Natural Products
Medications were traditionally given in the form of herbal mixtures. Many traditional medicines are still taken this manner. Science progressed throughout time such that chemists could extract increasingly powerful chemicals from natural sources. Willow tree bark was employed in ancient herbal treatments to produce aspirin (acetylsalicylic acid).
It’s common for chemical to come to the rescue when a natural supply is unavailable. The anticancer medication paclitaxel (Taxol) was discovered to be produced by the Pacific yew tree (Taxus brevifolia) in the early 1960s. Initially, the harvesting procedure removed the bark off the trees and killed them, resulting in a drop in Pacific yew populations. This technology was developed in response to public outrage, which allowed paclitaxel to be synthesised by chemically separating portion of the molecule from European yew needles. Today, paclitaxel is made by separating plant cells from branches and needles, then cultivating the cells in a process known as plant cell fermentation. This method is more environmentally friendly since it does not require trees and produces less chemical waste.
Drug Discovery: High-Throughput Screening
High-throughput screening is a common initial step in current drug development, in which thousands of compounds are evaluated simultaneously for their potency against a specific therapeutic target. Small quantities of prospective medications and drug targets are mixed by robots in this technique. Natural and man-made molecules might be included in the collection of test molecules. By attaching to the target biomolecule (i.e. the key to the lock) or killing sick cells, a molecule might show promise as a medication during the screening phase. A prospective medicine is developed from an effective molecule discovered in this manner by screening more variations of the original molecule. A drug’s human behaviour may be mimicked in cells and animals, if a more powerful molecule is discovered. The next phase is a clinical trial if the medicine is successful in laboratory testing.
Phase Two: Clinical Trials
A drug’s impact on people is evaluated through clinical trials, which are part of the development process. It is necessary to conduct clinical trials in small groups of patients before FDA approval is granted for the general public since the human body is more complicated than a single cell. A set of chemical structure-based predictions were constructed to anticipate the “druglikeness” of a molecule. Although these metrics are not mandatory, they may provide a good approximation of how the medication acts in the body (e.g., toxicity) and how the body responds to the molecule (e.g. metabolism, absorption) []. []. As part of clinical trials, the drug’s effectiveness in treating the ailment it’s supposed to treat and its safety for usage by patients are the primary goals. There are typically billions of dollars spent in the discovery and development of a medicine in this second phase; this massive expenditure is a significant element of the inherent financial risk in drug development.
In certain cases, a drug’s intended use is not its most effective use. When sildenafil (Viagra) was first created, it was intended to treat both high blood pressure and angina. Although clinical studies had demonstrated that Viagra was unsuccessful in treating angina, patients started begging for the medicine during its initial clinical trial. A second clinical trial was conducted to examine the effects of Viagra on erectile dysfunction, and eventually, Viagra became the billion-dollar medicine it is today.
Challenges Going Forward
New genetic and illness-identification tools will enhance our knowledge of the molecular underpinnings of disease. Unfortunately, the pharmaceutical industry’s capacity to discover cures seems to be outpacing the pace at which new illnesses emerge. The emergence of resistance in some disease-causing bacteria, viruses, parasites, and malignancies may also make treatments useless. As an example, Staphylococcus aureus (Staph) may grow resistant to numerous medications, such as amoxicillin. Multidrug-resistant Staphylococcus aureus (MRSA) is the common name for these staph strains, which need the administration of powerful antibiotics like vancomycin (commonly referred to as the “drug of last resort” due to its kidney-damaging side effects). Sadly, vancomycin-resistant staph (VRSA) strains have evolved in the past 15 years and constitute a huge challenge to drug scientists since further stronger medicines must be produced.
It’s obvious that pharmaceutical researchers need to step up their efforts to find viable treatments for these emerging ailments. There has also been a decline in the number of pharmaceutical businesses that have invested in research and development in recent years. As a result of this urgent need, the federal government established a new drug development facility inside NIH to help meet this problem front on. Only time will tell whether the present approaches to drug development are successful in generating workable cures.
