Clinical studay approval
Assuming the company receives FDA go-ahead, the company will move the drug on to Phase 1 testing in human subjects. At this point, the compound has a one in five chance of eventually reaching the market, and will normally take another five to nine years to reach that destination.
Phase 1
Phase 1 trials concentrate on developing the drug's safety profile. The human subjects in the study are normally healthy volunteers, though sometimes patients who have terminal illnesses and have no other therapeutic alternative will take part in Phase 1 studies as well. The sample is normally not more than 100 patients in Phase 1. The basic goal of Phase 1 is to determine how the drug is absorbed, distributed in the body, metabolized, and excreted. The duration of the drug's effects are also measured. Phase 1 testing ranges from one to three years, on average.
Assuming the data from Phase 1 are positive and the safety of the compound is established, the drug moves on to Phase 2 testing. If the company moves on to begin Phase 2 trials, the drug's chance of eventually making it to market improves to just under 30%.
Phase 2
Phase 2 trials consist of small, well-controlled experiments to continue to evaluate the drug's safety and assess side effects. The drugs are given to volunteers (usually between 100 and 300 patients) who actually suffer from the disease or condition being targeted by the drug. This phase is where the optimal dosage of the drug is established. Also, statistical end points are established for the drug that represent the targeted favorable outcome of the study. The current standard of care for the medical condition can be used as a benchmark in setting the end point. Phase 2 trials last an average of two years.
A drug that moves on to begin Phase 3 testing has about a 60% chance of actually being approved by the FDA.
Phase 3
Phase 3 testing is intended to verify the effectiveness of the drug against the condition that it targets, based on the statistical end points established in Phase 2. The study also continues to build the safety profile of the drug and record possible side effects and adverse reactions resulting from long-term use. Phase 3 studies are tightly controlled, double-blind studies with a sample size of at least 1000 patients. If the drug proves to be effective in this stage, the trial is deemed successful (pivotal). Normally two pivotal trials are required to ensure the validity of the studies, although if the results are extremely strong, one may suffice. Phase 3 testing averages between three and four years.
Assuming the drug reaches the desirable end point in Phase 3 trials, the company will then file a New Drug Application, which can contain 100,000 pages of data supporting the efficacy and safety of the drug. At this point, the drug has better than a 70% chance of being approved by the FDA.
Approval of the NDA can take anywhere from two months to an extreme of several years (in the case that the FDA requests additional information), with an average wait of between 18 and 24 months. Upon approval, the company may begin to market and distribute the drug.
Phase 4
Once the drug is on the market, the company must continue to perform observational studies in an ongoing evaluation of the drug's safety during routine use. The company also attempts to monitor any usage of the drug for conditions other than the approved medical indication. If the drug is being successfully used for off-label indications, the company will often initiate further clinical trials for those indications in order to widen the potential market for the drug.
What are the odds of approval? Based on the Advisory Committee [AC] vote of 13 to 4, the odds seem to be quite high. Moreover, surveying the outcomes of the recent FDA Advisory Committees, the FDA has approved 37 of the last 38 treatments following a positive recommendation from an Advisory Committee. The current FDA commissioner is a urological oncologist and prostate cancer survivor whose father passed away from AIPC, who has publicly stated more than once that FDA will serve as a “bridge” to new cancer therapy and not an obstacle, and has gone on record as saying that cancer can be conquered by 2015.
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