On Tuesday, January 3rd, BIO submitted comments in response to the Food and Drug Administration’s (FDA) recent draft guidance containing recommendations for sponsors on monitoring growth and evaluating pubertal development in clinical trials which enroll pediatric participants. As planning, conducting, and recruiting for clinical trials that involve pediatric patients can be challenging, BIO is appreciative to FDA for developing clear recommendations that sponsors can refer to when developing and operationalizing their clinical protocols. To make the guidance more broadly applicable, BIO suggested FDA consider expanding on the topic of body proportionality, especially for rare conditions associated with disproportionate stature or measurements. Furthermore, though the examples of measurement tools FDA provides in the guidance are useful, some may not be available at all sites. To overcome this issue, BIO requested that the Agency maintain flexibility around the specific tools sponsors use. Lastly, BIO suggested that including recommendations on which timeframes offer the most meaningful data for specific growth and development measurements (e.g., clarification on whether 12 months is sufficient to provide clinically meaningful information for growth and development) would be beneficial to sponsors.