Q1 2023 Onconova Therapeutics Inc Earnings Call
Participants
Mark Patrick Guerin; CFO & COO; Onconova Therapeutics, Inc.
Michael E. Saunders; Interim Chief Medical Officer; Onconova Therapeutics, Inc.
Steven M. Fruchtman; CEO, President & Director; Onconova Therapeutics, Inc.
Ahu Demir; MD & Senior Research Analyst; Ladenburg Thalmann & Co. Inc., Research Division
Joseph Pantginis; Director of Research & MD of Equity Research; H.C. Wainwright & Co, LLC, Research Division
Robert Michael LeBoyer; VP of Research & Analyst of Life Sciences; NOBLE Capital Markets, Inc., Research Division
Bruce Mackle
Presentation
Operator
Ladies and gentlemen, thank you for standing by. Welcome to the Onconova Therapeutics First Quarter 2023 Financial Results and Business Update Conference Call. (Operator Instructions) As a reminder, this call is being recorded today, May 15, 2023.
At this time, I would like to turn the call over to Bruce Mackle of LifeSci Advisors.
Bruce Mackle
Thank you, operator, and welcome, everyone, to Onconova's First Quarter 2023 Financial Results and Business Update Conference Call. Earlier this afternoon, Onconova issued a press release reporting its financial results and business progress. If you have not yet seen this press release, it is available in the Investors and Media section of the company's website at onconova.com. Following my introduction, we will hear from Onconova's President and CEO; Dr. Steve Fruchtman; Interim Chief Medical Officer; Dr. Michael Saunders; and Chief Operating Officer and Chief Financial Officer, Mark Guerin. Onconova's VP of Regulatory Affairs and Quality Assurance, Fred Frullo, will also be available during the Q&A session following the prepared remarks.
Before we begin, I would like to remind everyone that statements made during this conference call will include forward-looking statements under the safe harbor provisions of the Private Securities Litigation Reform Act of 1995, which involve risks and uncertainties that can cause actual results to differ materially. Forward-looking statements speak only as of the date they are made as the underlying facts and circumstances may change. Except as required by law, Onconova disclaims any obligation to update these forward-looking statements to reflect future information, events or circumstances.
For more information on forward-looking statements, please review the disclaimer in today's press release and the risk factors in the company's SEC filings.
With that, I will now turn the call over to Onconova's President and CEO, Dr. Steve Fruchtman.
Steven M. Fruchtman
Thanks, Bruce, and thanks to all for listening. Before we provide our update, I would like to take a moment to remember our late Chief Medical Officer, Dr. Mark Gelder. Mark made many valuable contributions to Onconova and had a very distinguished career as a biomedical innovator and oncologist, dedicated to advancing the care of patients with female reproductive cancers. We continue to work tirelessly to on his memory through the advancement of our clinical programs, endometrial and other cases. And we are immensely grateful for the time we got to spend together.
In addition to a colleague, we lost a friend and a very good man. Although big shoes to fill, Dr. Michael Saunders, our Interim Chief Medical Officer, is an amazing clinical scientist with a remarkable track record of success in developing some of our most innovative therapeutics for patients with advanced cancer. I want to thank Michael for his efforts during these very difficult past few weeks.
For our update today, we will focus primarily on 2 topics. The first will be the progress of our ongoing Phase I/IIa trial of narazaciclib combined letrozole in low-grade endometrioid endometrial cancer, which, as announced this week, had the first patient dosed on the study.
The second point will be our planned regulatory interactions around rigosertib's Phase II program in RDEB or recessive dystrophic epidermolysis bullosa recessive associated squamous cell carcinoma, which were the subject of a FDA Type B meeting request. These development highlights brought -- was a very productive quarter for Onconova.
For those interested in details on our progress in our additional clinical and preclinical programs, I encourage you to see our recent press releases detailing key meetings where our science is presented, including our earnings release issued earlier today.
With that, I'll introduce our Interim Chief Medical Officer, Dr. Michael Saunders. As I stated, but it is worth repeating Michael is a deeply experienced drug developer with extensive knowledge of our programs, thanks to his work as a consultant to Onconova for over the past 2-plus years. Prior to this, in the most recent role was as Executive Director of Drug Safety and Pharmacovigilance for Array BioPharma and Pfizer. Michael, please go ahead with the update.
Michael E. Saunders
Thank you for that very kind introduction, Steve. I'll begin my portion of today's call by reporting that narazaciclib has continued to display an acceptable safety profile in the Phase I monotherapy trial evaluating a continuous daily dosing schedule in participants with solid tumors.
Patients are on the 240-milligram cohort, and as we dose escalate, we are starting to see the effects of CDK 4/6 inhibition on bone marrow function, telling us we are engaging our targets but without seeing any clinically meaningful cases of neutropenia or diarrhea, which are dose-limiting toxicities associated with the FDA-approved CDK 4/6 inhibitors among additional toxicities seen with agents targeting a variety of CDK pathways.
These findings suggest narazaciclib may overcome the safety and tolerability shortcomings of these agents and indicate the Phase I program has accomplished its objective of providing the information needed to confidently advance our program to the next stage of development, which we already initiated in the trial of narazaciclib in combination with letrozole in endometrial cancer. Thus, during the next stage, we will evaluate the safety and efficacy of narazaciclib-based combinations in specific indications.
With those familiar with our plans, the first indication we are targeting is recurrent low-grade endometrioid endometrial cancer or LGEEC. Last week, the first patient was dosed in a Phase I/IIa trial in this indication, which is on track for a preliminary data readout in the fourth quarter of this year. Recurrent LGEEC was chosen as narazaciclib's first target indication because it marries a clear need for improved therapies with what we believe is a high probability of technical and regulatory success.
Based on Compendia listings, patients with recurrent LGEEC are currently treated off-label with letrozole combined with 1 of the CDK 4/6 inhibitors, palbociclib, ribociclib or abemaciclib, which are approved only for the treatment of hormone receptor-positive HER2-negative breast cancer. While these Compendia listings are based on the results of both single-arm trials in a randomized study that demonstrated improved clinical benefit based on the improvement in progression-free survival with the combination of letrozole and palbociclib versus letrozole alone, it's clear that the off-label combinations currently employed are marked by short timings related to safety, tolerability and treatment resistance.
We believe narazaciclib has a high probability of technical and regulatory success in LGEEC because like palbociclib, ribociclib and abemaciclib, it inhibits CDK4 and CDK6 with high potency. However, in addition, we also potently target a novel protein Bob-1. The overexpression Bob-1 has been correlated with poor outcomes in certain cancers, including breast and endometrial cancer. This data was presented at the recent AACR meeting in Orlando. Therefore, the narazaciclib, letrozole combination targets, endometrial cancer with a mechanism of action for which clinical proof of concept has been demonstrated.
It is worth repeating that in addition to targeting CDK 4 and 6 narazaciclib inhibits kinases not targeted by the aforementioned commercially available agents. These include a variety of important kinases such as the previously mentioned Bob-1 which also -- which was shown in a presentation at AACR last month to be associated with poor survival and a key subtype of endometrial cancer. Narazaciclib's ability to target these additional kinases such as CSF1R and ARK 5 together with the clinical safety findings to date, I referenced earlier, fuel our belief that a narazaciclib-letrozole combination can provide LGEEC patients with a much improved treatment option.
Beyond LGEEC, we continue to evaluate opportunities for combination studies of narazaciclib and additional indications and presented data at AACR last month that provide evidence of its potential to combine synergistically with a variety of therapeutic agents and additional indications. We expect to begin at least 1 additional combination study of barazaciclib by the end of the year. and we'll provide additional details once the clinical protocol is finalized.
Next, I'd like to speak about rigosertib's investigator-sponsored Phase II program in advanced squamous cell carcinoma, complicating, recessive dystrophic epidermolysis bullosa, or RDEB-associated SCC as it is often referred to. The most recent data from this program show that both initial and evaluable patients achieving complete clinical responses of all cancerous skin lesions.
The responses are durable. We're seeing with either intravenous or oral rigosertib administration, and rigosertib has been well tolerated with no additional toxicities in this subset of cancer patients with an unusual defect of having genomic mutations of Collagen VII. This data was presented last week at the International Society of Investigational Dermatology meeting with enormous interest from the international experts in the disease.
Excitingly, new additional patients were identified at the meeting to be consolidated onto or considered on to study entry. These patients are ultra rare, and we are very pleased to have identified additional patients whom we hope rigosertib will be as helpful to as with the patients already treated to date.
While these data are only from 2 patients, it's important to realize that RDEB associated SCC is an ultra-rare disease with extraordinarily high unmet need. The cumulative risk of death is tragically 70% by the age of 45. Once recurrent metastatic squamous cell cancer occurs following surgery, it is almost always invariably fatal with no effective treatment options. Because of this high and urgent unmet need, we believe the most prudent next step for the program is to discuss our early findings with regulators to determine the optimal most expeditious path towards an NDA filing and potential approval.
In this regard, we have requested a Type B meeting with FDA. Based on regulatory time lines associated with the Type B meeting, we expect to provide an update on rigosertib's regulatory pathway and RDEB-associated SCC in the third quarter. After we have completed the Type B meeting and received written feedback.
Notably, rigosertib's results in RDEB-associated SCC may have positive read-through into more prevalent indications as a key driver of the disease is PLK1, a kinase that is overexpressed in other cancers and is potently inhibited by rigosertib.
To further explore this possibility, we recently began collaborating with Pangea Biomed to use their proprietary tumor intelligence platform to identify biomarkers that could predict patient response to rigosertib. This platform makes predictions by evaluating in vitro preclinical and clinical data sets to build genetic social networks that reveal tumor vulnerabilities to specialize -- to specify therapies.
These analyses are focused both on Rigosertib's ability to inhibit PLK1 as well as the other pathways targeted by its multifaceted mechanism of action. The results of these collaborative analyses may then inform an artificial intelligence-driven precision medicine approach towards selectively identifying additional indications and biomarkers for rigosertib's potential efficacy evaluation.
The last studies I'll speak about today are 2 investigator-sponsored trials evaluating rigosertib in combination with checkpoint inhibition. The first of these studies, I'll mention is the Phase II trial evaluating rigosertib combined with KEYTRUDA in checkpoint blockade, refractory metastatic melanoma. Enrollment recently opened in this study, which is being conducted in collaboration with investigators at Vanderbilt University Medical Center, who are sponsoring the trial and Merck through supplying KEYTRUDA.
And lastly, I'll provide a brief update on the Phase I/IIa trial of rigosertib combined with Bristol Myers Squibb's OPDIVO in KRAS mutated non-small cell lung cancer patients who have failed prior therapy with PD-1 checkpoint inhibition. This trial continues to recruit patients at the dose featured in our most recent data update on the trial, namely 560 milligrams twice daily for 3 weeks on and 1 week off, which was presented at ESMO last year and showed an encouraging signal of efficacy with a studied (inaudible) across multiple KRAS mutations.
Based upon these results as well as an acceptable safety data, from the trial to date. The protocol has been amended so that we can assess further increasing the dose of rigosertib in the trial, which will lead to an enhanced efficacy signal as well as continued acceptable safety. We plan to present data on patients receiving the increased dose of rigosertib alongside a broader update from the trial. Taking into account the time needed to enroll patients on the higher dose, we now expect to report updated data from the trial in the second half of this year.
With that, I'll conclude my remarks and my portion of the call and hand it off to Mark.
Mark Patrick Guerin
Thank you, Mike. Onconova closed the first quarter of 2023 with cash and cash equivalents of $34.2 million compared to $38.8 million as of December 31, 2022. Based on our current projections, we believe that our cash position will be sufficient to fund our ongoing clinical trials and business operations, pass key clinical and regulatory milestones and into the first quarter of 2024.
Research and development expenses for the first quarter of 2023 were $4.1 million compared to $2 million for the first quarter of 2022. General and administrative expenses for the first quarter of '23 were $2.1 million, and this compares with $2.2 million for the first quarter of 2022. Net loss for the first quarter of 2023 was $5.8 million or $0.28 per share on 20.9 million weighted shares outstanding. This compares with a net loss for the first quarter of 2022 of $4.1 million or $0.20 per share on 20.9 million weighted shares outstanding. The increase in net loss for the first quarter of 2023 compared to '22 was primarily a result of narazaciclib clinical development and manufacturing expenses in the 2023 period.
With my financial overview complete, I'll now hand the call back to Steve for his concluding remarks.
Steven M. Fruchtman
Thanks, Mark. I'll conclude by reminding listeners that we have seen remarkable efficacy data with rigosertib in RDEB squamous cell carcinoma, and very encouraging data across various KRAS mutations in KRAS-mutated non-small cell lung cancer.
Our progress has us on track to achieve several important clinical and regulatory milestones this year. These include: one, the first readout to establish the combination dose from our Phase I/IIa trial of narazaciclib combined with letrozole in endometrial cancer; two, an important regulatory update on rigosertib's RDEB-associated squamous cell carcinoma program; and three, updated efficacy and safety data to include additional patients from the Phase I/IIa trial of rigosertib plus OPDIVO in non-small cell lung KRAS-mutated cancer.
We are on track for these milestones due to the hard work of our employees, partners and investigators, and mostly due to the bravery and dedication of our clinical trial participants. I thank each of these individuals for their important contributions.
With that, we will begin today's Q&A session. And operator, I will turn it over to you, and thank you.
Question and Answer Session
Operator
(Operator Instructions) Your first question comes from the line of Joe Pantginis of H.C. Wainwright.
Joseph Pantginis
But first, let me offer my condolences for the big shock of Mark's loss. It was great for the team. It was a great man. So very sorry to hear that.
So first, I wanted to ask about naraza's profile here. So as you're looking to push the dose in the Phase I and dosing within the LGEEC study, I was just curious, will or when or will you expect to eventually see the hematologic adverse events or and/or will you expect still some lessened impacts on the adverse event profile due to how the drug hits the kinome tree.
Steven M. Fruchtman
Well, thank you, Joe. I'll take that question. And the answer is you don't really know until you continue to dose escalate. Well, we're already starting to see some minor decreases in total white counts and AAC of the patients. So that's why we believe we're getting close -- and for that reason, translating the monotherapy trial of narazaciclib, -- we've already opened the doublet trial. We usually -- as you know, you wait for the recommended Phase II dose before you do combination studies.
But to expedite our time lines, because as you follow the white cat, you could start to see a decrease -- we recognize that we're probably getting close and thus is able to open the endometrial cancer trial in combination at 1 dose back from where we were when we started that study at NYU. That rationale makes perfect sense as -- as we get close to the single-agent recommended Phase II and therefore, we'll expect that our understanding, which is the most important question because your drugs are always given in combination with anti-estrogens. And we're already doing that in the NYU Phase I endometrioid trial.
Joseph Pantginis
Got it. Got it. And switching over to rigosertib for RDEB-associated SCC. Obviously, the big thing we're looking for, as you've mentioned, is the feedback from your Type B meeting, and we discussed this previously, but if you wanted to highlight again some of the wish list coming from that.
But the main part of my question is, looking beyond to potential commercialization and even pivotal study before that, that is patient identification what's the process you're going through? Obviously, it's an ultra-orphan indication. Are you working with? Or will you be working with organizations like DEBRA that really have the pulse of the RDEB population or the DEB population?
Steven M. Fruchtman
Yes, Joe. So it's amazing to me how rapidly you become an expert in whatever the science and the clinical information that the companies you cover. So DEBRA is the main international not-for-profit involved in this disease. The leadership of DEBRA typically has children who suffer from RDEB and at the meeting that we just presented in Osaka in Japan, DEBRA was very well present there. Many of the investigators including ourselves, by the way. And you know this, our trial coming out of Philadelphia is supported by DEBRA.
So the experts in the world who are all present in Osaka were very impressed with a disease that's invariably may lethal once a recurrent squamous cell occurs, not just the fact that it's lethal, no therapeutic maneuvers work. And the responses we've seen with rigosertib in my humble and clinical opinion are totally remarkable, but you could have these massive fungating cancer to disappear.
So based on the responses we're seeing, as Michael said, regarding to interact with the agencies, show them our data because what we really need is guidance from the agency in an ultra-rare disease with a tremendous unmet medical need, how many patients would they like for us to have to get an approval.
And the other thing that came out of Osaka, we've already identified additional patients throughout the world because the caregiver for these patients were all present in Osaka. That's another very important development for us to be able to put additional patients on and hopefully, preliminary results with either IV or oral, we sort of will continue to be as extraordinary as we've seen in the patients put on the study to date, and we will have more patients with this disease treated with rigosertib.
Operator
Your next question comes from the line of Ahu Demir of Ladenburg.
Ahu Demir
Congrats on the quarter. And in addition, my condolences on Mark's as well. It was a pleasure to work with him.
A few questions from us. First one is on the narazaciclib program. Could you comment on the CDK 4/6 activity in the endometrial cancer as we know, I think it's not approved, but it is used in a patient. So if you could maybe provide some color on the percentage of patients who are treated with CDK4. And also, are the patients excluded if they had CDK 4/6 treatment previously?
Steven M. Fruchtman
So I cannot comment. I think your question is how many patients in the U.S. are treated off label with the FDA approved CDK4/6 inhibitors, I do not know the number. I know certainty that the CDK 4/6 inhibitors are prescribed how many patients in the U.S., I do not know. But there are many similarities between breast cancer and endometrial cancer, especially the subtype we are studying.
They are both hormonally driven. That's why they're giving in combination with antiestrogen, and there have been clinical trials, and that's why they're used off-label, suggesting that the progression-free subviral of the combination or a CDK4/6 inhibitor, specifically palbociclib plus letrozole prolonged PFS 2.5 to 3x what it was with letrozole alone.
But the clinical data in a randomized trial supports our approach -- the fact is it does not have FDA approval in this indication. And we believe because these tumors are driven by CDK 4 and 6, are driven by estrogen as is breast cancer that our logic is good to pursue the endometrial cancer space, and we're excited by our first patient. We anticipate the recommended Phase II dosing of the combination should be done before the end of this year.
Ahu Demir
That's helpful, Steve. And are those patients are excluded each patient received CK46 previously? Are they excluded in the trial?
Steven M. Fruchtman
The answer is I do not believe they are because we believe we differentiated who based on it could have been given, let's say, 1 of the CDK 4/6 inhibited and they stopped it, for instance, due to safety concerns, be that neutropenia or diarrhea and because we target -- we're differentiated also because we target resistant pathways in these diseases, patients who have failed the FDA-approved CDK 4/6 inhibitor will be permitted on a trial because, again, the goal is to get the dose.
It's really not an efficacy trial. It's really to get the optimal dose of the combination, not necessary to study efficacy in a Phase I study with no control arm.
Operator
Your next question comes from the line of Robert LeBoyer of NOBLE Capital Markets.
Robert Michael LeBoyer
First, I'd like to offer my sympathies on Dr. Gelder's loss to the company and to family.
My question has to do with the solid tumor trial and whether the time frame for announcing results has been established and what you're expecting going forward?
Steven M. Fruchtman
Rob, you said a solid tumor trial? Are you speaking both of narazaciclib and rigosertib? I could take both. I'm not sure which compound you're asking about.
Robert Michael LeBoyer
I was speaking of narazaciclib, but please take both.
Steven M. Fruchtman
Sure. Thanks, Robert. So we anticipate the recommended Phase II dose in endometrial cancer, as I mentioned before the end of the year. Once we have that dose, then our plan will be to initiate a randomized pivotal Phase III trial in the same indicate in studying narazaciclib plus letrozole versus letrozole alone, and we anticipate beginning that trial early in 2024.
Regarding rigosertib in non-small cell lung cancer, probably similar time lines. This will be more of an exploratory trial. We're very encouraged by a complete response and partial responses seen in highly refractory KRAS-mutated d non-small cell lung cancer. And as we've discussed previously, not just the interesting response rate that we're seeing, but the fact that we are mutant agnostic. We have responses in at least 3 different KRAS mutations, which there is no other drug that is FDA approved that does that.
As you know, the approved drugs only target G12C, approximately 20%, 25% of all patients that have a mutation of G12C so the 70% to 80% of the other patients have other mutations that we hope to target. We anticipate that study also coming to completion in 2024 -- I'm sorry, in 2023 by the end of the year.
But as Michael mentioned, because of safety appears to be very accepted with the combination of rigosertib and nivolumab, we may make a decision to continue to dose escalate the rigosertib to doses that we have not given to patients previously, I can't predict the safety profile, but we really want to make sure we have optimized the efficacy for this combination, and we believe by increasing rigosertib if the safety permits us to do that, we will be confident that we will have the most efficacious dose of the combination.
Operator
I'm showing no further questions at this queue.
Steven M. Fruchtman
Operator, if I can interrupt you. I realized and I thank Joe for not stopping me. I didn't answer both on Joe's questions, and I'd like to take an opportunity to do so. Okay. Joe has also asked about commercialization regarding squamous cell RDEB, and I didn't answer that question. I'd like the opportunity to do so, Joe.
Operator
Go ahead, sir.
Steven M. Fruchtman
It's really so clearly, our goal would be to get rigosertib approved in this ultra-rare disease just to get rigosertib the value, of the value of rigosertib we think is extremely valuable to Onconova. After the previous studies done, we believe and have stated many times, we believe we're on the right path by studying squamous cell complicating RDEB, the -- [quite of the science] that brought us here.
But in addition to this very rare disease, they were more common squamous cells of humanity also due to damaged skin it's just that the spontaneous squamous cells not complicating RDEB, but the damaged skin is from thunder, for instance, patients who have to too much sun exposure may also develop squamous cell carcinoma.
All the squamous cell carcinomas exist as well, squamous cell of the lung, which is probably due to other environmental toxins that we inhale, that damage the lungs, the cervical squamous cell as well. So there's a variety of squamous cells that we did a more common that we can attempt to address.
And the question that we're working on with both Pangea and other sources because there's no approved PLK1 drug approved, pathology labs are not typically testing for the over expression of PLK1, but we plan to look at what percentage of squamous cells irregardless of the histological site, lung, skin, cervix, et cetera, what -- and neck as well, which I neglected to say, what is the overall percentage of PLK-driven squamous cell because that is a group we'd be very interested in studying and that a group such as that would be a very large commercial success, we believe.
Operator
I'm showing no further questions in the queue. At this time, I'd like to turn the call back to the speakers for any closing remarks.
Steven M. Fruchtman
Well, thank you all for participating in today's call. We are pleased to be approaching very important milestones across our pipeline and look forward to providing additional updates as they are achieved. Thanks again for participating and have a great evening. Goodbye.
Operator
Ladies and gentlemen, thank you for your participation on today's conference call. This concludes today's event. You may now disconnect.
