It is now my pleasure to turn the conference over to Louise Barrett, Senior Vice President, Legal Affairs.
Thank you, Drew. Good morning, and welcome to the Iterum Therapeutics Phase 3 REASSURE Clinical Trial Results conference call. A press release with our top-line results was issued earlier this morning and can be found on our website. The press release also has a link to the webcast, and if you're not using the webcast, the slides we'll be referencing are available on our website, www.iterumtx.com, under the heading Investors and Events and Presentations. Also filed as an exhibit to our current report on Form 8-K filed this morning with the SEC. We are joined this morning by our Chief Executive Officer, Corey Fishman, our Chief Medical Officer, Dr. Sailaja Puttagunta, and our Chief Financial Officer, Judy Matthews. Corey will provide some opening remarks. Sailaja will provide some more data on the results of our study, and then we will open the lines for Q&A.
Before we begin, I would like to remind you that some of the information presented on this conference call will contain forward-looking statements concerning our plans, strategies, and prospects for our business, including the development, therapeutic, and market potential of oral sulopenem, our ability to address the deficiency set out in the Complete Response Letter received from the FDA in July 2021. The expected timing of resubmission of our NDA, the expected timing of review of the NDA by the FDA, and the company's strategic process to sell, license, or otherwise dispose of its rights to sulopenem to maximize stakeholder value.
Actual results may differ materially from those indicated by these forward-looking statements as a result of various factors outside of our control, including uncertainties inherent in the design, initiation, and conduct of clinical and non-clinical development. Changes in the regulatory requirements or decisions of regulatory authorities.
The timing or likelihood of regulatory filings and approvals, including the potential resubmission of our NDA for oral sulopenem. Changes in public policy or legislation. The accuracy of our expectations regarding how far into the future our cash on hand will fund our ongoing operations. Our ability to maintain our listing on the NASDAQ Capital Market. Risk and uncertainties concerning the outcome, impact, effects, and results of Iterum's pursuit of strategic alternatives, including the terms, timing, structure, value, benefits, and costs of any strategic process and our ability to complete one at all. The other factors discussed under the caption Risk Factors in our quarterly report on Form 10-K, filed with the SEC on November 14, 2023. In addition, any forward-looking statements represent our views only as of the date of this call and should not be relied upon as representing our views as of any subsequent date.
We specifically disclaim any obligation to update such statements. With that all said, now I'll turn you over to Corey for your opening remarks.
Thanks, Louise. Welcome, and thanks for joining us today. First and foremost, I want to share some very exciting news. We are very pleased to announce positive data from our confirmatory phase 3 clinical trial in uncomplicated urinary tract infections, which was conducted under Special Protocol Assessment agreement with the FDA. Results demonstrate that oral sulopenem was non-inferior to Augmentin with respect to the trial's primary endpoint, which was overall response, which is the combined clinical cure plus microbiologic eradication at the test of cure visit in the Microbiological Modified Intent-to-Treat susceptible population. Very importantly, I'd like to thank all of the patients and physicians that participated in the REASSURE trial. Now I'll turn the call over to Dr. Sailaja Puttagunta, our Chief Medical Officer, for a bit more data on the results of our study.
Thanks, Corey, and good morning, everyone. On Slide 3, you'll see that REASSURE is a randomized, multicenter, double-blind, active control study that randomized 2,222 adult women with uncomplicated UTI in a 1:1 manner to receive either oral sulopenem or oral Augmentin twice daily for 5 days. An end of treatment visit occurred on day 5. The primary endpoint of overall response was measured on day 12 at the test of cure visit. The final study visit occurred on day 28. Slide 4 shows that the primary endpoint for this study was overall response, which was combined clinical success as well as microbiologic eradication. Clinical success in this study was defined as resolution of all baseline UTI symptoms and the absence of any new UTI symptoms.
Microbiologic eradication was defined as a urine culture with less than 10 to the 3 colony-forming units per mL of the baseline uropathogen. The primary objective of the study was to establish non-inferiority of sulopenem compared to Augmentin in the Augmentin-susceptible population at the test of cure visit on day 12. Slide 5 highlights the results for the primary endpoint of overall response at the test of cure visit in the micro-MITT for Augmentin- susceptible population. 61.7% of patients who received oral sulopenem achieved overall success, compared to 55% of those that received Augmentin. The difference in success rates between the two treatment groups was 6.7%, and the lower bound of the 95% confidence interval around the treatment difference was 0.3.
Non-inferiority of oral sulopenem over Augmentin was established as the lower bound of the 95% CI was above -10%... and superiority was concluded as the 95% confidence interval did not include zero, and an ad hoc p-value was 0.02. Slide 6 shows that oral sulopenem also demonstrated consistent efficacy for all key secondary endpoints at the test of cure visit. Similar proportions of patients in each treatment group achieved clinical success, about 77%, while a higher proportion of patients in the sulopenem treatment group attained microbiologic success, 75%, relative to the 67% observed in the Augmentin treatment group. Slide 7 highlights that sulopenem demonstrated a consistent safety profile in this study relative to previous sulopenem phase 3 studies and similar to other beta-lactam antibiotics.
Both oral sulopenem and Augmentin were well tolerated in this study, with less than 1% of patients discontinuing treatment due to adverse events. Overall, 19% of patients in the sulopenem arm and 4% in the Augmentin arm reported an adverse event. Drug-related adverse events were reported by 14% of patients in the sulopenem group, relative to 8% in the Augmentin group. There were no serious adverse events in the sulopenem treatment group, while five patients in the Augmentin group reported serious adverse events, though none of them were thought to be drug-related. There were no deaths in either treatment group in this study. The most common adverse events reported were diarrhea, nausea, and headache, similar to those reported in the previous phase 3 uUTI study.
In conclusion, sulopenem was well tolerated with an adverse event profile consistent with beta-lactam antibiotics, and no new safety signals were identified for oral sulopenem in this study. I'll stop here now and turn the call back to Corey.
Thanks, Sailaja. On Slide 8, you'll see that as Sailaja covered, we achieved our primary endpoint in this study by demonstrating that sulopenem was non-inferior to Augmentin in the overall response at the test of cure in the Augmentin-susceptible population. Additionally, in this population, sulopenem also demonstrated statistical superiority. Oral sulopenem also showed consistent efficacy in secondary and additional endpoints. Lastly, sulopenem demonstrated a very solid safety profile. In terms of next steps, we expect to resubmit our New Drug Application for oral sulopenem in Q2 of this year, and provided that the resubmitted NDA addresses all of the deficiencies identified in the complete response letter we received from the FDA in July 2021, we expect the FDA will complete its review and take action in the fourth quarter of this year, which would be six months from the date the FDA receives the resubmitted New Drug Application.
Let's spend just a minute and talk about market dynamics. The uncomplicated urinary tract market is quite large, estimated at over 30 million infections annually. There is a significant need for new, efficacious, and safe oral products to treat uncomplicated urinary tract infections, as the existing older oral products are experiencing high and increasing resistance rates, as well as exhibiting subpar safety profiles. If approved, sulopenem would be the first oral penem approved in the United States and one of the first new branded treatments approved in the US for uncomplicated urinary tract infections since the turn of the century. With positive data now in hand, we will be focusing on a strategic process to sell, license, or otherwise dispose of our rights to sulopenem, with the goal of maximizing value for our stakeholders.
We're excited about potentially having sulopenem in the hands of patients and physicians in the underserved, uncomplicated urinary tract infection market. We'll now open the lines for Q&A.
Thank you. We will now start today's Q&A session. If you would like to ask a question, please press star followed by one on your telephone keypad now. If you change your mind, please press star followed by two. Our first question today comes from Jason McCarthy from Maxim Group. Your line is now open. Please go ahead.
Good morning, Corey and team. Congratulations on the data. Corey, can you talk a little bit about the outcome ending up being also superior on the primary endpoint? And if that's related to issues with resistance to Augmentin already, which is one of the standard therapies for UTIs, and how sulopenem can really impact clinical outcomes if it gets approved or when it's approved?
Sure. Actually, it's kind of interesting, Jason. Thanks for the question, first of all, because sulopenem hit the non-inferiority, as we talked about in the susceptible population and was statistically superior, but that was in the susceptible population. So it's actually even a little bit different, and I would say a little bit more favorable because we're not talking about the resistant population. Those are patients that had a bug that was susceptible to Augmentin, and in that population, we were both non-inferior and statistically superior in that population.
Will the full data set be stratified by a resistant population as well as it had been in the prior study? Or is it because they are in the same class as lactams, that you don't need to do that?
Yeah. The resistant population in the study ended up being very, very small, and I believe we only had something on the order of 67 patients that were resistant, and therefore, no conclusions can be drawn from a sample size that small. So we may look at that, but I don't think there's any conclusions that can be drawn just because the sample size is as small as it is.
Got it. Last question. In terms of your commercial readiness, can you talk just a little bit about a lot of that readiness and kind of legwork that was done prior with expectations of approval in 2021, and what you'll need to do to kind of ramp that up should sulopenem get approved later this year?
Yeah, I think, I think the commercial side, as you said, had quite a bit of work done previously, and I think the real, the opportunity for doing some more on the commercial is really just an update or a refresh of the data that was done, the research that was done, and talking with, you know, payers, just confirming what we had already found out previously. And clearly that, you know, all of that information is valuable in any scenario that we would, we would take forward, you know, be that in a potential transaction, be that on your own. All of that is always gonna be important for getting the product ready to hit the market and have a, a very good, solid uptake.
Thank you, Corey. Congrats on the data.
Thanks, Jason.
Just to remind everyone, if you would like to ask a question, please press star followed by one on your telephone keypad. If you change your mind, please press star followed by two. We have no further questions at this time, so I will hand back over for any closing remarks.
Great. Thanks very much. We appreciate you joining us today on this call. We are very excited by the results that oral sulopenem has demonstrated in our REASSURE trial, and we're looking forward to resubmitting our new drug application and working with the FDA during the review period, with an eye toward potentially having this important treatment in the hands of patients and physicians in the underserved market of uncomplicated urinary tract infections. Have a great day.