THE PILL BUILT TO REPLACE INFIGRATINIB: TYRA-300

[Dausa]

TYRA-300 / dabogratinib: why people are watching it in achondroplasia​

For education only — not medical advice. TYRA-300 is investigational and is being studied in clinical trials.

1. What is TYRA-300?​

TYRA-300, also called dabogratinib, is an oral drug designed to block FGFR3. In achondroplasia, FGFR3 is overactive and acts like a brake on bone growth.
The goal is to reduce that overly strong FGFR3 signal and support more normal growth-plate activity.
Achondroplasia and FGFR3

2. What makes it different?​

The main point of TYRA-300 is selectivity.
Infigratinib blocks FGFR1, FGFR2, and FGFR3. Erdafitinib blocks FGFR1 through FGFR4. TYRA-300 was designed to focus much more strongly on FGFR3.
BEACH301 trial record for dabogratinib / TYRA-300

3. What does FGFR3 do in achondroplasia?​

FGFR3 slows bone growth. In achondroplasia, the signal is too active, which affects growth plates and can lead to shorter long bones and differences in skeletal development.
The idea behind an FGFR3 inhibitor is to take some pressure off that “brake.” In preclinical research, reducing FGFR3 activity has been associated with improved growth-plate function and bone growth in achondroplasia models.



FGFR3 biology in achondroplasia

4. Where does TYRA-300 stand today?​

TYRA-300 is being studied in the BEACH301 Phase 2 trial in children ages 3–10 with achondroplasia and open growth plates.
The study is looking at dose, safety, tolerability, and early signs of whether the drug supports growth. It is not yet a completed late-stage trial, so the clinical picture is still developing.
Official BEACH301 study details

5. How does it compare with infigratinib?​

Infigratinib has more advanced achondroplasia data and blocks several FGFR receptors, including FGFR3. TYRA-300 is earlier in development but was designed to be more focused on FGFR3.
The central question being tested is whether that precision can preserve the desired growth effect while limiting effects from blocking FGFR1, FGFR2, or FGFR4.
That is why TYRA-300 is getting attention: it is not trying to be a broader FGFR drug. It is being developed as a more targeted FGFR3 option.