Gossamer Bio, Inc. Q1 FY2020 earnings call

GB001 - Once - a - day oral DP2 antagonist

• Completed a pre - specified interim analysis for the LEDA Phase 2b study of GB001 in moderate - to - severe eosinophilic asthma, with the IDMC recommending the study continue as planned. Commenced initial Phase 3 planning and supportive activities.
• In the Phase 2 TITAN study for chronic rhinosinusitis, enrollment has been completed and expects topline data in the second half of 2020. Implemented mitigations for COVID - 19 including virtual study visits, direct - to - patient drug supply and remote monitoring.
• United States Patent and Trademark Office issued a new patent protecting aspects of the key drug substance forms being studied in clinical development of GB001.

GB004 - Potential first - in - class gut targeted oral HIF - 1 alpha stabilizer for IBD

• Phase 1b study in active ulcerative colitis showed GB004 was well - tolerated, with most common adverse events being mild. Observed target engagement in the gut, including increase in genes consistent with enhanced epithelial barrier function and reduction in myeloperoxidase. Saw favorable trends on exploratory efficacy outcomes, such as mucosal healing and histologic remission in the GB004 arm compared to placebo. Plan to commence a 12 - week induction study in the second half of 2020 with the tablet form of GB004. Amended license agreement with Aerpio Pharmaceuticals, reducing milestone obligations and royalties.

GB002 - Inhaled PDGFR inhibitor for pulmonary arterial hypertension

• Ongoing dose ranging Phase 1b trial in PAH patients had enrollment temporarily paused due to COVID - 19, shifting guidance for initial data from Q2 to the second half of 2020. Anticipate beginning enrollment in the second half of 2020 for the Phase 2 study.

GB1275 - Oral CD11b modulator for solid tumors

• Continues to advance through dose escalation in the Phase 1/2 KEYNOTE - A36 trial, with no dose limiting toxicities observed. Will present initial data in solid tumors at the ASCO Virtual Meeting and updated data in the second half of 2020. Received orphan drug designation from both EMA and FDA for the treatment of pancreatic cancer.

Corporate update

• Dr. Jakob Dupont will depart as Chief Medical Officer in June 2020, with other executives taking over his responsibilities. Gossamer has put procedures in place to minimize risks from COVID - 19, with most operations continuing unabated.

As of the end of the first quarter of 2020, Gossamer Bio had $346 million of cash and cash equivalents. Research and development expense in the first quarter of 2020 was approximately $41.4 million compared to $25 million in the same period of 2019. In - process R&D expenses in the first quarter of 2020 were approximately $2.8 million compared to $1 million in the same period of 2019. G&A expenses were $10.7 million in the first quarter compared to $8 million in the same period of 2019. The net loss for the quarter was $54.1 million, equating to $0.87 per share, while in the same period of 2019, the net loss was $32.6 million, equating to $0.90 per share.

GB001

• After the interim analysis of the LEDA study, commenced initial Phase 3 planning and supportive activities. The topline data for GB001 in both asthma and chronic rhinosinusitis studies are expected in the second half of 2020.

GB002

• Phase 1b trial enrollment paused due to COVID - 19, shifting guidance for initial data from Q2 to the second half of 2020. Phase 2 study of GB002 anticipated to begin enrollment in the second half of 2020.

GB004

• Plan to commence a 12 - week induction Phase 2 study in the second half of 2020 with the tablet form of GB004, barring unforeseen delays from COVID - 19.

GB1275

• Will present initial data in solid tumors at the ASCO Virtual Meeting and updated data in the second half of 2020.

COVID - 19 impact

• The ongoing COVID - 19 pandemic may adversely affect the timely initiation and completion of clinical studies, as well as the timely release of results from clinical trials. For example, enrollment in GB002's Phase 1b trial was temporarily paused due to COVID - 19, and the推进 of other studies may be affected.

Q: Can you give us a little more insight into what went into that interim go - no - go decision for GB001? Was there a level of clinical reduction that was met that really ultimately drove that recommendation? And when you think about success in the Phase 3, are you looking for some more thresholds versus what was met in that Phase 2 interim?

A: Whilst the interim was pre - specified and planned as an administrative analysis, looking at the totality of the data on primary and key secondary efficacy endpoints, safety and tolerability. The IDMC, a seasoned group of pulmonary and respiratory experts, took a look at that data and made a determination. The Phase 3 decision will be based on the totality of the final data and discussions with global regulatory authorities. We're looking at the totality of the data set for the final Phase 3 decision, including efficacy endpoints, secondary endpoints, safety and tolerability.

Q: Just in terms of the UC data, can you help us think about what the next steps would be for GB004 in terms of thinking about the potential next study? And I guess, what data you would want to see to further derisk the asset before you'd be comfortable moving forward into a Phase 3 study? And then secondly, on the UC program, I guess, just in terms of your pre - clinical modeling or perhaps maybe from the initial clinical data, what is the JAK in terms of the length of time it would take to get to sort of the peak efficacy?

A: We're very pleased with the Phase 1b data and will be doing a more robust Phase 2 induction study of 12 weeks, looking at additional outcome measures such as clinical response remission and continuing to look at mucosal healing and the effect on histology. Based on pre - clinical colitis models and Phase 1 normal healthy volunteer studies, we can guide our dose escalation. Typically, we see earlier effects on histology then you could see on some of the other clinical parameters. So we feel comfortable with the 12 - week induction period as it gives us enough time to evaluate induction effects.

Q: Can you maybe just talk now as you think about that sort of go - no - go decision in going into potentially into a Phase 3? Just kind of where you're sort of setting the internal bar from a high level in light of the obvious Novartis data late last year? And I guess to follow - up on that question as well. Maybe just kind of clarify then around when we get the topline data, it sounds like we may not get a go - no - go decision at that point. Is that kind of where the -- our expectation should be set?

A: The intention of the GB001 program is to be an oral treatment for moderate - to - severe asthma. We're looking to see a good impact on clinical exacerbation, which is the approvable Phase 3 endpoint. We've been talking about a range of 20% to 30% exacerbation reduction. We'll continue to monitor and measure, and the final Phase 3 decision will be informed by the totality of the final data, interactions with global regulatory authorities, and learning from other programs like Novartis'. We may not get a go - no - go decision at topline, but will have more information to make an informed decision.

Q: Great, thanks for taking the questions. And I had a few questions on GB002. So, I know recently, I think earlier this year, Acceleron had some positive data with their compound, sotatercept. And I know that was a Phase 2 study where they looked at PVR in six - minute walk distance. I think they also have another study where they're looking at oxygen consumption. So, I guess my question is, do you think you need to look at anything else besides PVR in six - minute walk distance in terms of secondary or exploratory endpoints to help ensure a competitive profile for 002 in PAH?

A: The key endpoints for PAH approval are six - minute walk distance and reduction in pulmonary vascular resistance. CPET is being used in exploratory to see if it can add additional information, but it's too early to say it can be used in the absence of the other endpoints. We're focused on safety, tolerability, target engagement, biomarker and pharmacodynamic work, and some exploratory outcome measures in the Phase 1b study to guide dose selection for Phase 2.