Hair loss affects millions and often resists standard treatment. A new compound, PP405, is showing promise – but is it too soon to celebrate?
M has always struggled with low self-esteem because of his baldness. He had tried various treatments – minoxidil, finasteride, and even splurged on expensive hair regrowth therapies, but nothing worked for him. He’s far from alone. Hair loss is something that many people are quietly struggling with, and it goes beyond appearance.
Hair loss affects millions worldwide. It can be caused by genetics, ageing, stress, or underlying medical conditions. Hair loss is more than just a cosmetic concern. It can deeply impact a person’s confidence and self-worth.
A new compound known as PP405 has recently sparked interest in the scientific community and among those battling hair thinning or balding. Could this be a game-changer that we’ve been waiting for in hair loss treatment?
What is PP405?
PP405 is a novel molecule that is being explored for its potential to stimulate hair regrowth. It is formulated be applied topically on the scalp.
Unlike oral medications or blood flow enhancers, PP405 is designed to act directly on the scalp – targeting hair follicles and potentially jumpstarting them back into the growth cycle.
Understanding the Hair Growth Cycle
Hair growth consists of anagen (growth), catagen (transitional) and telogen (resting) phases.
- Anagen phase is the active stage in which hair grows.
- Catagen phase is the short, transitional phase where hair growth slows down and the hair follicles begin to shrink.
- Telogen phase is the resting phase where hair follicles remain dormant and hair growth halts.
In people with androgenetic alopecia (also known as pattern baldness), their hair follicles shrink and spend less time in the growth phase before entering the resting phase too soon. Androgenetic alopecia is the most common type of hair loss and baldness in both males and females.
How Might PP405 Work?
Although it is still in development, PP405 is drawing attention as it appears to have a different mechanism of action from the current therapies.
Early studies suggest PP405 may:
- Activate dormant hair follicles stem cells.
- Convert hair follicles from telogen (resting) phase back to anagen (growth) phase of the hair growth cycle.
Is PP405 Clinically Proven?
In a randomised, multicentre and double-blind phase 2a trial involving 78 patients aged between 18 to 55 years, researchers evaluated the safety, pharmacokinetics and effectiveness of PP405 in adults with androgenetic alopecia.
The participants were randomly assigned to use either 0.05% PP405 topical gel or a placebo gel once daily for four weeks. They were then followed up for up to 12 weeks. After that, they could join an open-label extension study for another three months to assess the long-term safety.
Here’s what the trial found:
- Phase 1 trial found using 0.05% PP405 topical treatment once daily for seven days is safe and tolerable.
- 31% of men with more advanced hair loss who used PP405 saw more than 20% increase in hair density at 8 weeks, compared to 0% in the placebo group.
- PP405 was also well tolerated, with no signs of systemic absorption into the bloodstream.
How Is PP405 Different from Existing Treatments?
Unlike existing hair loss treatments like minoxidil or finasteride, PP405 works in a different mechanism.
| Treatment | Mechanism of Action | Side Effects | Formulation |
| Minoxidil | Improves blood flow to hair follicles. |
| 2% or 5% topical solution or foam. (Approved for both men and women. Typically, 2% for women, and 5% for men) Off label use: Oral minoxidil |
| Finasteride | Blocks the 5-alpha-reductase enzymes that converts hormone testosterone to dihydrotestosterone (DHT). DHT is linked to hair loss. |
| 1 mg oral tablet. (Approved for men only.) |
| PP405 | Potentially stimulates hair regrowth. | Still under study. | 0.05% topical gel is under study. |
A Glimmer of Hope
For those who have exhausted traditional treatments without success, PP405 may represent a new hope. Its early performance has shown much promise – but it is still undergoing trials, and much remains to be studied before it reaches clinic shelves.
If you are facing hair loss, speak with a healthcare provider or dermatologist about what options are available today, and perhaps PP405 may be on your radar in the future!
External references
- Physiology, Hair. National Library of Medicine. Updated: 30 July 2023. https://www.ncbi.nlm.nih.gov/books/NBK499948/
- Male Pattern Baldness (Androgenetic Alopecia): Why Does It Occur? Medical Channel Asia. Updated: 21 June 2022. https://medicalchannelasia.com/male-pattern-baldness-androgenetic-alopecia-why-does-it-occur/
- What’s All The Fuss About PP405 & Can This Molecule Really Treat Baldness? City Skin Clinic. Updated: 27 May 2025. https://cityskinclinic.com/pp405-molecule-hair-regrowth/
- Faculty in the News – Michael Jung. UCLA. Updated: 11 July 2024. https://www.chemistry.ucla.edu/news/faculty-in-the-news-michael-jung/
- Regenerative Medicine in Action: Topical PP405 Shows Promise in Androgenetic Alopecia. The Dermatology Digest. Updated: 17 June 2025. https://thedermdigest.com/regenerative-medicine-in-action-topical-pp405-shows-promise-in-androgenetic-alopecia/
- Recent Advances in Drug Development for Hair Loss. Int J Mol Sci. 2025 Apr 8;26(8):3461. https://pmc.ncbi.nlm.nih.gov/articles/PMC12026576/
- Oral Minoxidil: A Game Changer for Hair Loss Treatment. Medical Channel Asia. Updated: 23 June 2023. https://medicalchannelasia.com/oral-minoxidil-a-game-changer-for-hair-loss-treatment/
