Spero Therapeutics, Inc. (NASDAQ:SPRO) Q2 2023 Earnings Call Transcript

Sath Shukla: We haven’t disclosed that as stated. But what we can tell you is that our colleagues at GSK have set a target commercialization date for tebipenem for 2026. So, obviously as you look backwards through a trial readout and an NDA process, you can draw your conclusions about the expected length of the trial. But we have also stated in the past is that we expect this trial to be larger than ADAPT-PO to ensure that the clinical data we would want – we would get would be sufficient, positive and persuasive to reach approval. So, the last trial took roughly 9 months to 12 months to enroll. This will be longer than that with constrained with the target timeline that we are working towards.

Boobalan Pachaiyappan: Great. Thanks for the clarity. And then of [indiscernible], how is tebipenem performing commercially these days in Japan?

Sath Shukla: It’s something that we don’t track on an active basis because it’s in a different indication entirely, which is pediatric pneumonia. And it’s been there since 2009, so 14 years and we feel that the performance of that drug in Japan has limited application for a different tablet form in at agilely different indication. But from what we know, going along well. At this point, to our understanding, millions of patients have been dosed and the drug has performed well.

Boobalan Pachaiyappan: Okay. Great. And then thirdly, this is probably a lengthy question. So, please confirm or deny whether meaningful milestones are likely to be payable to Spero from GSK upon achievement of the following a, enrollment of the first patient into the tebipenem Phase 3 trial, b, achievement of 50% enrollment in the tebipenem Phase 3 trial and c, completion of enrollment of this – in this trial.

Sath Shukla: Well, I think on a macro level, I can confirm that those payments will come through, through the beginning duration and ending of the trial. We haven’t disclosed very specific timelines and milestones on those. With that said, this will become self-evident over a period of time when – as we continue to report out the company’s progress as well as the cash influx into the company, you will gain a greater visibility into what achievements trigger these milestones and the timing of those milestones. But beyond our disclosures at this moment in time, we are not providing any deeper data at the moment.

Boobalan Pachaiyappan: Okay. Great. And then do you have any updated market research or epidemiological information with respect to 720 commercial opportunity in the U.S.? If so, what does this show?

Sath Shukla: Yes. What we have said in the past is roughly 100,000 patients domestically in the U.S., roughly 0.25 million patients in major markets worldwide. That includes Japan, where as Kamal pointed out earlier, the prevalence is very similar to that of the U.S. That continues to be at least from a top line perspective, our assessment of the market opportunity. What I would note is at least for the current trial, that is in first-line patients, which is three quarters roughly of that population. So, you are looking at somewhere approaching 200,000 patients for that market opportunity. Beyond that, just like our other stakeholders, we continue to evaluate a rising and more available epidemiological information and promos [ph] information and are tracking usually the growth rates in the diagnosis of the disease for future planning purposes. But at this stage, I think our findings are fairly consistent with what we have reported at before.

Boobalan Pachaiyappan: Thanks so much for taking our questions, congrats again.

Sath Shukla: Thank you.

Operator: This concludes – we have another caller on the line. The next question comes from Ritu Baral with Cowen. Please go ahead.