Gossamer Bio, Inc. Q3 FY2021 earnings call

• Discussed seralutinib's TORREY Phase II study, with enrollment impacted by COVID-19 but confident in completing enrollment and reaching top line data in second half of 2022.
• Announced completion of enrollment for GB004's SHIFT-UC Phase II study in mild-to-moderate ulcerative colitis, with top line results expected in first half of 2022 and treat-through endpoints in fourth quarter of 2022.
• Unveiled new CNS-Penetrant BTK inhibitors GB5121 and GB7208, with GB5121 dosed in Phase I trial in healthy volunteers this month and GB7208 expected in first-in-human trial in second half of next year.

For seralutinib, the top line data readout for the TORREY Phase II study was shifted to the second half of 2022 due to COVID-19 challenges. For GB004, enrollment for the SHIFT-UC Phase II study in mild-to-moderate ulcerative colitis was completed, with top line results expected in the first half of 2022. Financials: Ended Q3 2021 with $366 million of cash and cash equivalents. Research and development expenses were approximately $43.2 million in Q3 2021 vs $41.8 million in Q3 2020. G&A expenses were $12.5 million in Q3 2021 vs $11.4 million in Q3 2020. Net loss for the quarter was $60.2 million, equating to $0.80 per share, compared to a net loss of $57.8 million in Q3 2020 ($0.80 per share).

• Shifted TORREY Phase II top line data readout to second half of 2022.
• GB004 SHIFT-UC Phase II top line results expected in first half of 2022, treat-through endpoints in fourth quarter of 2022.
• GB5121 dosed in Phase I trial in healthy volunteers; expect to initiate potentially registrational Phase Ib/II trial in first half of next year.
• GB7208 expected in first-in-human clinical trial in second half of next year.

• Impact of ongoing COVID-19 pandemic on timely initiation and completion of clinical studies, including enrollment and release of trial results.
• Uncertainty around clinical trial timelines due to potential resurgence of COVID-19 variants or continued disruptions in medical professional availability.

Q: Yasmeen Rahimi asked about the number of patients in OLE for TORREY and site status for top line data, and about statistical hierarchy in SHIFT-UC secondary endpoints.

A: Faheem and Bryan responded on site status and Richard Aranda discussed secondary endpoints in SHIFT-UC.

Q: Joseph Schwartz inquired about characterization of second half 2022 for TORREY data release and enrollment rate impact.

A: Faheem and Bryan discussed ongoing COVID impact and confidence in plan despite variables.

Q: Carter Gould asked about satisfaction with SHIFT-UC population and UC landscape impact.

A: Faheem and Richard Aranda commented on market tailwind and targeted patient population.

Q: Olivia Brayer asked about efficacy measures in TORREY study and updates on UC.

A: Richard Aranda stated expected efficacy guideposts remain the same.

Q: Unidentified Analyst asked about GB5121 enrollment pace and GB7208 study.

A: Richard Aranda discussed Phase I study design for GB5121 and similar plans for GB7208.

Q: Unidentified Analyst asked about GB5121 inclusion criteria for PCNSL and GB7208.

A: Faheem discussed inclusion of patients with intraocular or CSF involvement and study design for GB5121.

Q: Unidentified Analyst asked about OLE updates for seralutinib and vascular remodeling.

A: Faheem discussed OLE status of seralutinib patients and lack of specific vascular remodeling assessments.