Jonathan Zalevsky
Analyst · JPMorgan. Your line is open
Thank you, Howard. Starting with REZPEG, this program is the most advanced IL2 Treg mechanism in the field. We believe there are major opportunities in both atopic dermatitis and alopecia areata that REZPEG could potentially address. Our Phase 1b REZPEG data in atopic dermatitis demonstrated dose dependent efficacy and encouraging durability observed long after patients completed the 12-week induction period. In fact, for both patient reported outcomes and physician assessed endpoints, we observed the same trends rapid onset of effect, dose dependence and long-term durability of control. The rapid onset of action and the type of extended disease control after the end of dosing rivals are outperformed of dupilumab or JAK inhibitors. And these promising data have us and physicians very enthusiastic about the potential for long lasting responses and infrequent maintenance dosing with REZPEG in atopic dermatitis. As Howard mentioned, last month we published preclinical and clinical REZPEG data in Nature Communication. The manuscript includes results from mouse models and two human Phase 1b studies in atopic dermatitis and psoriasis, all demonstrating the potential of REZPEG for the treatment of inflammatory skin diseases. The clinical results from these two different inflammatory skin conditions showed that REZPEG improved physician assessed disease activity and patient reported outcomes. These promising findings clinically validate the Treg hypothesis that causally restoring Treg function through a central pathway of IL2 receptor driven Treg Rescue can have therapeutic potential across a variety of chronic skin diseases. It also demonstrates that REZPEG can act on multiple disease driving pathways and is uniquely poised to address a diversity of immunopathology. Furthermore, a consistent safety and tolerability profile was observed across the studies and in line with previously published data. The exciting cross indication clinical efficacy we observed is buttressed by serum biomarker analysis demonstrating that REZPEG can modulate multiple immunoregulatory pathways to provide rapid onset and duration of efficacy. In the atopic dermatitis study, we included longitudinal serum proteomics analysis and it demonstrated the plural virality of Treg mediated pathways with potential effects on tissue resident memory T-cell population, resulting in sustained efficacy seen in the antigen challenged mouse models and in the clinical trial. These proteomic findings further validate our therapeutic approach of using a Treg stimulator to dampen inflammatory responses and simultaneously restore immune balance in patients with chronic inflammatory skin diseases. Overall, the totality of the observations, including the biomarker analysis, provide an understanding of how treatment with REZPEG led to dose dependent efficacy in the Phase 1b study over the 12-week treatment period including its rapid onset of action and it also provides insight into pathways that could result in the sustained efficacy that was observed in the study even after treatment was removed. And all of this supports the design of our ongoing Phase 2b study in atopic dermatitis which is enrolling roughly 400 patients with moderate to severe disease across three different regimens of REZPEG versus placebo evaluated over a 16-week induction period. After the induction period, patients that meet a threshold to advance from induction to maintenance will be rerandomized into one of two maintenance regimens at their original dose level to receive that dose level on either a once a month or once every three-month regimen. The maintenance portion of the study is 36 weeks which will in total provide 52 weeks of treatment duration for patients in the study. We will also follow participants for one year after the conclusion of the 52-week treatment period enabling us to evaluate the potential remittance effects of REZPEG. Enrollment is on track and approximately 130 clinical investigator sites are active across the US, Canada, Europe and Australia. As Howard mentioned, we anticipate top line data from the 16-week induction period of this Phase 2b study in the first half of 2025 and data from the 36-week maintenance period of the study will be available towards the end of 2025 or early 2026. Now turning to alopecia areata which is a dermal disease localized to hair follicles. In this disease the patient's immune system attacks the hair follicle disrupting its normal ability to keep and grow hair leading to hair loss. We believe there is strong rationale for REZPEG in this indication based on the role of T-regs on the underlying pathology of the disease. The Phase 2b study is well underway and plans to recruit 84 patients with severe to very severe disease that will be randomized to REZPEG or placebo. Patients will be treated for a period of 36 weeks and observed up to 60 weeks in total. Our primary endpoint for this study is mean percent improvement in SALT or the severity of alopecia tool at week 36 and we expect top line data in the second half of 2025. Now turning to NKTR-0165 our TNFR2 agonist antibody. TNFR2 is highly expressed on T-regs, myeloid suppressor cells, regulatory B cells, neuronal cells and others. In T-regs, TNFR2 agonist has been shown to potentiate the effector functions, suppressive functions and maintenance of Treg lineage stability, especially in the non-lymphoid tissue compartments. Genetic studies show that if TNFR2 is absent, the phenotypic effect is autoimmunity as well as other conditions that resemble FOXP3 loss of function. In contrast, its presence and activation of its signaling has been associated with immunoregulatory function and tissue protection effects. Our TNFR2 agonist program is built upon many years of Treg experience that we've gained from studying REZPEG. REZPEG as you know, as an IL2 receptor pathway agonist drives JAK STAT signaling in Treg, which is critical to drive Treg proliferation and function in primary and secondary lymphoid organs. TNFR2, on the other hand, is the most abundant TNF superfamily member expressed on Tregs and a key activator of NF Kappa B, which also controls the FOXP3 protein expression and is critical to maintain Treg function, especially in the non-lymphoid organs. Thus, with the REZPEG and TNFR2 agonist programs, Nektar's pipeline provides target rationale for both lymphoid and non-lymphoid Tregs and this is one of the reasons why we are so excited about NKTR-0165. We presented the first preclinical data for this program at EULAR in June of this year and there were several key takeaways from that presentation. First, the TNFR2 agonists we discovered are able to signal through the TNFR2 multimeric receptor, single arm monovalent antibody which is a very novel effect for a TNFR2 agonistic antibody. Second, the clinical candidate NKTR-0165 demonstrated very high specificity for binding and signaling through TNFR2 on Tregs with little to no binding and signaling in conventional T-cells, NK cells or monocytes. Third, NKTR-0165 is a monotherapy drove Treg proliferation upregulation of FOXP3 and other activation markers of primary human Tregs. Fourth, the PKPD of NKTR-0165 and efficacy in the KLH DTH model were confirmed in a human TNFR2 knock in mouse model. We are very excited with the unique and differentiated profile of the antibodies that were discovered and we are rapidly advancing NKTR-0165 into the clinic and we expect to submit an IND for this program in the second half of 2025. Examples of indications that could be addressed include multiple sclerosis, mucosal immunology conditions such as ulcerative colitis, and even dermal autoimmune diseases such as vitiligo. Now, since the TNFR2 agonist antibody specificities we discovered are active at stake single arm antibodies, we have leveraged this to design a pipeline of TNFR2 containing bispecific molecules that pair TNFR2 agonism with other specificities. These novel assets take advantage of multiple mechanisms to bring about novel molecules with novel approaches for targeting autoimmune diseases. We look forward to provide more color on this pipeline as development candidates emerge for future clinical entry. Overall, we have observed growing interest for a novel and selective TNFR2 agonists like NKTR-0165 and as we move forward with our IND enabling studies as well as with our progression of the bispecific pipeline, we will continue to be open to the opportunity of working with companies that have interest in these areas to strategize on the best path forward. We have a second preclinical target in the immunology space, PEG CSF1 called NKTR-422. This program is a PEG modified hematopoietic colony stimulating factor protein. Current standard of care, Chronic inflammatory disease therapies are designed to suppress inflammation and are not optimized for inflammation resolution and the restoration of tissue homeostasis tissue function. The goal of NKTR-422 is to stimulate inflammation resolution and tissue repair by targeting the expansion, reprogramming and activation of anti-inflammatory tissue resident macrophages. An agent that possesses such biological properties could create a new class of anti-inflammatory therapeutics and this is our objective with NKTR-422. To discover NKTR-422, we used in vitro and in vivo screening of CSF1 PEG conjugates to identify a CSF1 receptor agonist with a differentiated PKPD profile compared to the native cytokine. And what we found was in vivo treatment with NKTR-422 shows significantly reduced target media clearance, sustained target engagement, durable signaling on both the ERK and AKT pathways, proliferation and expansion of tissue resident macrophages with minimal off target effects of monocyte infiltration or production of monocyte derived macrophages. Moreover, tissue macrophages induce the expression of inflammation resolution and tissue repair markers including increased IL4 receptor alpha, IL10 receptor alpha cell surface expression, spherocytosis receptor, MerTK regulation and metalloprotease activation. NKTR-422 monotherapy showed efficacy in the mouse CSS colitis model and combination treatment of NKTR-422 with etanercept greatly increased the efficacy of TNF alpha blockade on arthritic PAS swelling after starting treatment at the peak of inflammation in a rat collagen induced arthritis model. As Howard mentioned, data from our early research of this program has been selected for an oral presentation at this year's ACR Convergence Conference. This program has applications in a number of therapeutic indications that span acute and chronic inflammatory diseases and we're excited to be presenting this first preclinical data next week. And with that, I'll hand the call over to Mary to discuss NKTR-255. Mary?