 We all know how expensive medicines are, but how costly can it really be to make a pill? To answer this question, we need to understand the path of a medicine from the bench to the bedside. You may have heard the numbers. It takes an average of 12 years and 1 to 2 billion dollars to get a medicine to patients. Well, let's break these numbers down by following the journey of a molecule to becoming a medicine. Today we will not talk about the distribution of a drug, but instead we will focus on the cost of developing a medicine. It all begins in the basic science laboratory where scientists study the underlying biology of a disease. What changes to a cell or tissue causes this disease? And can we design a medicine to stop or reverse the effects of the disease? This is called the discovery stage. At this stage, thousands of compounds are screened, often in a petri dish or test tube, to determine if they have the desirable effect. One in a thousand medicines tested in the discovery step proceed to the next stage, development. If the medicine looks promising, the company conducts experiments in animals to determine the safety of the medicine and proof that it works. In the development stage, scientists also study how the medicine is absorbed, broken down, what is the best dose to give, and how to administer it. At this point, an important decision is made. Is there enough evidence of safety and efficacy to test this medicine in humans? If so, the company talks to FDA and gathers all of the information known about the drug to file an investigational new drug, IND application. Of course, a human will respond differently from a mouse, so clinical research requires lots of thought and planning. This is when things get complicated if they haven't already. Researchers at companies design and conduct clinical trials each with a specific purpose. Phase 1 clinical trials take about a year, test the safety of the medicine in healthy volunteers at low and high doses, and cost about $1-5 million. Phase 2 clinical trials take 2-3 years, test the safety and potential efficacy of the medicine in a small group of patients, and cost about $10-20 million. Phase 3 clinical trials are the most time-consuming and expensive, costing over hundreds of millions of dollars. They take 3-5 years and assess the safety and efficacy of the medicine in hundreds or thousands of patients. Keep in mind that sometimes multiple trials are needed to test a single compound. One in ten medicines tested at the clinical trial stage successfully completes all three clinical trial phases. Throughout this time, the company communicates with FDA about the safety results and the design and progress of clinical trials. At this point, the researchers can file a new drug application, NDA, which FDA will review. This application consists of everything we know about the medicine, every single piece of data from the discovery stage to phase 3 clinical studies. The company has to pay a large fee of a few million dollars to FDA to make this review possible. The review process takes up to one year, at which point FDA decides whether to accept or reject the application. If the application is accepted, the medicine can be marketed and sold in the United States. Now 12 years and 1-2 billion dollars later, one compound has been FDA approved because it was shown to be safe and effective for the treatment of a disease. Only one in every 5,000-10,000 medicines tested makes it to this point. The others failed because they were not safe or effective or didn't have the required properties. The cost to study each of them can only be recovered through the sale of the medicine that is approved and marketed. In order to fund the development of more treatments, the approved medicine needs to generate the revenue that can be used to support research on thousands of other compounds for the treatment of diabetes, colon cancer or cystic fibrosis. As you can see, the cost of developing a treatment can be very high. It includes millions of dollars spent on chemistry in animal studies, hundreds of millions spent on clinical trials, and the amounts not recovered from the 9 out of 10 drugs that are tested in humans but fail in development and never earn any revenue for the company. Now our journey takes us to the bedside, where a cancer patient is receiving an FDA approved life-saving therapy that they know is safe and effective to treat their disease. Looking back, this process is complex but worthwhile. A thorough and trustworthy investigation and review of the drug's properties ensures that the benefits of taking the medicine outweigh the risks. This rigorous process keeps patients safe. And the safety review continues as more patients take the medicine and more is known about its risks and benefits.