Understand the purposes of clinical drug trialling
Surely this should be pretty obvious, unless you're A-OK with heaps of people getting drugs that haven't been proven to be safe and effective...
Know the phases of clinical drug trials, the intention of each phase and what groups are recruited into them
Know the important characteristics that distinguish each phase, know the difference between observational and controlled trials and know how power and bias are managed in clinical trials.
There are four main phases, imaginatively named I, II, III and IV. Sometimes there is also a "phase 0."
- Initial human pharmacokinetic and pharmacodynamic studies. Very low doses are used.
- Finding the safe dose. Only a few healthy volunteers are tested. They are exposed to gradually increasing doses of the drug while being carefully monitored.
- Finding out if the drug might work. 10s to 100s of volunteers with the condition are tested. They are compared against some kind of control group to see if the drug has any benefit over placebo (or a drug that has been shown to work).
- Finding out of the drug works. Similar to phase II, but now many more participants with the condition are tested. The number tested is statistically determined using power calculations and whatnot. (I don't really understand the statistics, sorry.)
- Continuous safety testing. Once the drug is marketed, reports of adverse effects are collected. These are generally effects that are rare so they might not have shown up in the previous three phases.
Oh yeah, before I forget, I need to tell you the basic stuff about the differences between observational and controlled trials and whatnot.
Phase IV is an observational trial, where you are basically relying on reports and so forth. This might be biased because not all drug reactions may be reported, or perhaps people might report something as being a drug reaction when it was caused by something else. This is because unfortunately we are all human and prone to fallacies like "post hoc ergo propter hoc" (i.e. thinking that two things are related simply because they happened at the same time), confirmational bias (i.e. "I think vaccines are bad, therefore I'm going to be 100% vigilant for any sniffle or cough or mild change in behaviour that might be a 'vaccine injury'") and so on. However, observational trials like this are probably our best bet at observing drug reactions in an entire population.
Controlled trials, such as those done in phases II and III, attempt to avoid as much bias as possible. The gold standard is a double-blind placebo-controlled study. Double-blind means that neither the patient nor the doctor knows what drug the patient is getting- that's only revealed right at the end for the purposes of data analysis. Placebo-controlled means that the drug is either tested against a sugar pill or against a drug that's already shown to work. It might seem weird testing a drug against another drug, but sometimes that's our most ethical option. It's not nice to leave some people untreated with only sugar pills when there is an effective drug available. Speaking of ethics...
Understand the important ethical considerations surrounding human drug trialling and the function of a Human Research Ethics Committee
Ethics committees are important in making sure that researchers don't do unethical stuff, like take blood samples at kids' birthday parties *cough*Mr Andrew Wakefield*cough*. Here are the main criteria of the Human Research Ethics Committee in Australia. These criteria are probably pretty similar worldwide.
- Research merit and integrity: Is the experiment soundly designed? You don't want to put participants through a trial and then find out that your results don't mean anything because you had a crappy experimental design.
- Justice: All patients have equal chance of benefit or harm. So for example participants should be randomly selected for the placebo and experimental groups- you can't just put all your mates into one group and all the people you don't like into the other.
- Beneficence: Participants' well-being has priority. Be nice to your participants!
- Respect: Participation should be voluntary and participants should be free to leave the trial at any time.
Be aware of the purposes of the Trial Protocol, the Investigator’s Brochure and the Patient Information and Consent documents
This is basically all the stuff you have to submit to get an ethics approval. The Trial Protocol is basically outlining what you're going to do, the Investigator's Brochure includes as much information about the drug as is currently known and the Patient Information and Consent Documents are the handouts that you're going to give to the patients to let them know that participation is voluntary, they can leave at any time, yada yada yada.
Aaaaaaand I'm done! (Except I am going to have a bonus post or two... stay tuned!)
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