fbpx How Many Phases Do Clinical Trials For Hair Loss Treatments Have?
Book a FREE consultation  
For a free consultation or assistance, please call 020 7730 6666

Browse by Category

How Many Phases Do Clinical Trials For Hair Loss Treatments Have?


HairlossANSWERS - Click to Submit Your Query to Our Hair Loss Experts

Name: Dan

Question:  How many phases does a drug like CTP-543 need to go through before it can be approved and actually used by people either over the counter or by prescription?

Am I right in assuming that even if this drug was to work and be safe, it’s unlikely that it would be available any time soon? Thanks in advance.

Answer: Hi, Dan. When it comes to developing new hair loss medications, the clinical trial process is much the same as for other drugs. There are five stages in total – four before release and one after, although pre-clinical research is needed before the first phase can begin.

Hair Loss ResearchEach stage is known as a ‘phase’ and these range from Phase 0 to Phase IV. Every phase, except phase 0 which may be rolled into phase 1, must be successfully completed in order to proceed to the next. Phases I and II may be split into extra sub-trials, for example a Phase I trial may need to study different delivery systems of a drug to find what works best. In this case they could have Phase IA explore one method while Phase IB explores an alternative.

For some tests, Phase I and Phase II trials may be combined and phases can generally be repeated until a satisfactory outcome is achieved. This is why clinical trials can take many years to complete, and also accounts for why some trials are abandoned. Sometimes this can be due to a lack of funding but it can also be due to failing to pass the necessary safety, efficacy and tolerability requirements that each phase is designed to ensure.

Phase 0 is the first step when small doses of the drug are given to a small number of people – usually 10 – to see how long it stays in their system. This is a newly introduced phase that is required especially for investigational drugs, and is also known as ‘human microdosing studies’.

Phase I sees human trials featuring around 20 to 100 participants who are healthy and not affected by the condition the drug is designed to treat. This phase is to assess optimal dosing and does so by starting the volunteers on a low dose and slowly increasing it, as necessary, and recording results – both positive and negative. Once safe dosage levels have been successfully established, phase II can begin.

Phase II tests the drug on patients with the condition researchers are hoping it will treat. There are usually between 100 and 300 test subjects involved in trials at this stage. The results will indicate the drug’s potential efficacy.

Phase III involves testing the drug on people with the condition it is designed to treat, in the recommended doses, in order to assess its safety, therapeutic efficacy and tolerability. There will usually be 300 to 3,000 people treated during this phase, by both clinical researchers and their own GPs. On successful completion of phase 3, the drug will generally be approved by the necessary regulatory bodies – such as the UK’s MHRA and the FDA in America – and can then be brought to market.

Phase IV is known as ‘postmarketing surveillance’ and involves the long-term monitoring of the drug after its release.

The likely release dates for this particular trial are unknown as, as you can see, the phase 2 trial is currently on hold due to FDA concerns. Other JAK inhibitors that are being tested as potential treatments for Alopecia Totalis and Alopecia Universalis – the more severe iterations of alopecia areata – are said to have an estimated release date of 2021. This is, of course, based on the assumption that everything goes to plan and there are no complications during the rest of their testing periods.

The drug you are enquiring about, CTP-543, is designed to treat alopecia areata in its mildest form – where it causes patchy hair loss to the scalp only. There are already effective alopecia areata treatment courses available for this particular autoimmune disorder, which you may wish to investigate. At Belgravia we have helped many patients to regrow their hair in this way, by using topical applications of high strength minoxidil, alongside with various additional hair growth boosters, combined into a personalised treatment plan. As you will see from our Alopecia Areata Treatment Success Stories gallery, this option can be extremely impactful – and it’s available now!

The Belgravia CentreThe Belgravia Centre

The Belgravia Centre is the leader in hair loss treatment in the UK, with two clinics based in Central London. If you are worried about hair loss you can arrange a free consultation with a hair loss expert or complete our Online Consultation Form from anywhere in the UK or the rest of the world. View our Hair Loss Success Stories, which are the largest collection of such success stories in the world and demonstrate the levels of success that so many of Belgravia’s patients achieve. You can also phone 020 7730 6666 any time for our hair loss helpline or to arrange a free consultation.

Related Stories

Online Consultation

Submit an instant online consultation so that one of Belgravia’s hair loss specialists can diagnose your condition and recommend an effective course of treatment, wherever you live.