Gene Kinney
Analyst · RBC Capital Markets. Your line is now open
Thank you, Sandy. And thank you all for joining this afternoon. The pleasure to be here today to discuss our 2016 and recent accomplishment and the milestones we're looking forward to in 2017. On today's call, I will highlight the progress we've made on each of our clinical programs. Talk briefly about our key corporate accomplishment. And then turn it over to Tran for a review of our year-end financial results and 2017 financial guidance. Before we begin talking about the terrific progress we've made across our pipeline. I would like to first comment on one event in 2016 that we were distinctly said about and of course I'm referring to the loss of Dr. Dale Schenk, our Former CEO and Co-Founder. With Dale’s passing, we lost first and foremost a friend and the broader scientific community lost a true innovator who will missed Dale and will forever be indebted to the scientific legacy that remain. Following this profound loss, with credit to our Board of Directors and leadership team for quickly instituting our succession and strategic plan. We've been able to seamlessly advance the business. This progress is also thanks to the efforts of our talented and dedicated employees whose relentless pursuit of new therapies for patients drives our ability to steadily advance our programs. I'd also like to thank those of you on the call today and our entire biotech community for the outpouring of support during the time of Dale's passing. In addition to your very kind words many of you made generous donations to the charity designated by his family. To us, it serves to underscore how fortunate we are to work in biotech. It's an incredible community that puts people first. So thank you on behalf of the entire Prothena team and also on behalf of Dale’s family who appreciated the messages of condolence during a very sad time. Now I will turn to an overview of our 2016 key milestones and highlight what lies ahead in 2017 and beyond. As you know we focus on two areas of science where we have deep domain expertise protein misfolding or cell adhesion. In 2016, we reported positive data for each of our clinical programs in these areas. And continue to raise awareness of our novel antibodies through the publication and presentation of scientific results. We ended 2016 with the balance sheet that should enable continued development of both our clinical and preclinical programs as we seek to deliver differentiated protein immunotherapies to patients. I’ll next discuss our scientific programs in more detail and I'd like to begin with a high level review of our programs in the area of protein misfolding. And start with our most advanced program NEOD001 monoclonal antibody for the potential treatment of patients with AL Amyloidosis. There are two broad categories of amyloid disease, those in the periphery and those in the central nervous system. AL Amyloidosis is a peripheral amyloid disease, which is systemic, progressive and often fatal due to organ dysfunction. While there are other types of systemic amyloidosis, including the AA and ATTR amyloidosis, patients with AL Amyloidosis represent the majority of the systemic amyloidosis. AL Amyloidosis is a rare disease that affects between 30,000 to 45,000 patients with an annual incidence rate of 10,000 to 15,000 patients in the U.S. and Europe. In AL Amyloidosis, light chain proteins produced by clonal plasma cells misfold, aggregate, circulate through the body and deposited amyloid in VITAL organs, most commonly in the heart and kidney, but also in peripheral nerves and other organs. These circulating soluble aggregates and deposited amyloid can cause this function and ultimately organ failure and approximately two-thirds of all patients with AL Amyloidosis have two or more organs that are impacted by the disease. There are no approved treatments for AL Amyloidosis and for the majority of patients current treatment is limited to the use of cytotoxic chemotherapeutic agents. However, none of these treatments approaches target the soluble aggregate in deposited amyloid that drives organ dysfunction and failure. The goal of these treatments is to control the hematologic burden, and targeting clonal plasma cells to decrease the production of new light chain. The cytotoxic agents are often poorly tolerated and patients may become refractory to their effect and/or relapse. In addition, for patients who undergo these plasma cell-directed chemotherapeutic treatments approximately 75% of patients do not achieve adequate organ benefit, even if they achieve hematologic control. This is important because it exemplifies the principle in amyloid disease that simply focusing on decreasing new protein production maybe insufficient to provide patient benefit in most cases in the context of AL Amyloidosis for example, it is clearly hematologic control in the absence of organ benefit is have limited value to this patient population. The nature of the disease means that patients do not get better without intervention and will experience progressive organ dysfunction that often leads to death. For example when AL Amyloid builds up in the heart, it leads to a progressive restrictive cardiomyopathy with associated cardiac dysfunction. As such there remains a significant unmet need for a well tolerated therapy that can improve organ function and survival by directly neutralizing circulating soluble aggregates and clearing deposited amyloid from organs. NEOD001 is an antibody being developed as a disease modifying therapy for AL Amyloidosis that specifically targets the amyloid that drives organ dysfunction and failure. As immunotherapy, NEOD001’s proposed mechanism of action is the neutralization of misfolded light chain in circulation and clearance of deposited amyloid through immunotherapy mediated clearance or phagocytosis of the amyloid deposited on organs. NEOD001 is the first immunotherapy directly targeting AL Amyloidosis to receive fast track designation from the U.S. Food and Drug Administration. In 2016, we continue to advance our two pivotally designed studies of NEOD001 in patients with AL Amyloidosis in cardiac dysfunction and I will provide more detail on each of those studies in a moment. Also in 2016, Dr. Morie Gertz of the Mayo Clinic presented results from our Phase I/II study of NEOD001 in patients with AL Amyloidosis persistent organ dysfunction at two medical conferences. He presented interim data from this study in an oral session at the International Symposium on Amyloidosis in July, 2016, and also presenting data from the completed study in an oral session at the American Society of Hematology Conference in December of 2016. It's worth mentioning that this was presented as part of the first oral session at ASH entirely dedicated to AL Amyloidosis, which was great to see from the perspective of the growing awareness of this grievous disease. Has remainder, this Phase I/II study enrollment the total of 69 patients with AL Amyloisdosis in persistent organ dysfunction, including 27 patients in the dose escalation portion of the study and an additional 42 patients in the expansion phase. All over the patients in this study had been previously treated with plasma cell direct therapy and continue to experience organ dysfunction. In the expansion phase of the study, patients were rolled into three prospectively defined cohorts consisting of 15 patients with predominantly cardiac dysfunction, 16 patients with renal dysfunction and 11 patients with peripheral neuropathy. Over the course of this study, patients received more than 990 separate infusions of nearly one with mean treatment duration of 12.8-month. As demonstrated in the results NEOD001 continued to be safe and well tolerated with no dose limiting toxicities or anti-drug antibodies and no treatment related discontinuations or treatment related serious adverse events. Data from the study also demonstrated improvement in three organ systems, cardiac, renal, and peripheral nerve. Specifically the results of the best response analysis showed that 53% or 19 of 36 of the cardiac evaluable patients demonstrated a cardiac response and 64% or 23 of the 36 renal evaluable patients demonstrated a renal response. In addition, an improvement in peripheral neuropathy in patients from the prospectively defined peripheral neuropathy expansion cohort was demonstrated by a mean 35% decrease in the Neuropathy Impairment Score-Lower Limb or NIS-LL measured at month 10. Improvements in patient NIS-LL scores resulted in a response rate of 82% or nine of the 11 patients in the peripheral neuropathy expansion cohort where two of nine responders showed complete resolution of peripheral neuropathy as measured by NIS-LL. As Dr. Gertz pointed out in his presentations, this was the first time that improvement in peripheral neuropathy was seen in patients with AL Amyloidosis. These response rate achieved across three organ systems in our study compared favorably to published historical response rate in patients previously treated with plasma cell-directed therapy. Additionally, a post-hoc subset analysis of the NEOD001 Phase I/II study results demonstrated that organ responses were not related to the time or depth of hematologic response achieved from previous plasma cell-directed therapy nor were they related to the time or type of prior therapy. This analysis was also presented during the same AL Amyloidosis oral session at the ASH Conference in December by Dr. Michaela Liedtke from the Stanford University School of Medicine. Based on these positive data from the Phase I/II study, we remain confident in the design empowering of our two ongoing clinical studies, the PRONTO and VITAL Amyloidosis studies. Moving now to the PRONTO and VITAL studies, our enrollment efforts in 2016 allow us to remain on track with our previous guided timelines for both of these studies. The PRONTO study is a Phase IIb global registration directed randomized, double-blind, placebo-controlled trial enrolling previously treated patients with a primary diagnosis of AL Amyloidosis and cardiac dysfunction. Patients in PRONTO are being randomized on a one-to-one basis to receive either NEOD001 or placebo. Based on current enrollment status, we expect to be fully enrolled with 100 patients in PRONTO by the end of this month. As a patient focused Company and because of the grievous nature of this disease and a high level of interest in this study, patients already in screening will be allowed to complete the process and will be subsequently randomized provided that they meet eligibility requirements. Because of this we are likely to be over enrolled. Our maximum screening period by protocol is 28 days with an average screening time to date of approximately 19 days. Accordingly, we expect all patients in screening to complete that process sometime in March. This is a 12-month study and accounting for time for database lock and data analysis, we expect to announce results in the second quarter of 2018. The primary endpoint of the PRONTO study is cardiac test response is defined by a change in NT-proBMP. NT-proBMP is a widely clinically validated functional biomarker that predicts survival in patients with AL Amyloidosis following intervention it has been demonstrated by numerous retrospective and prospective studies. Demonstrating a significant effect on cardiac response as measured by NT-proBMP along with supporting secondary outcomes has the potential to expedite our development timeline and provide an additional opportunity to engage with European regulators. We also continue to closely follow the important work of the Amyloidosis Research Consortium or ARC as they continue their dialogue with regulators on this topic. Most recently in December of 2016, ARC reported the submission of draft guidance to the FDA on developing new therapies in AL Amyloidosis. Amongst other topics this guidance reiterated the AL Amyloidosis research community's assessment of the evidence for NT-proBMP as a segregate end point for clinical outcome and survival. Turning to the VITAL Amyloidosis study, we are also continuing to enroll this study which is a Phase III global registration randomized, double-blind, placebo-controlled study enrolling newly-diagnosed, treatment-naïve patients with AL Amyloidosis in cardiac dysfunction. We expect to fully enroll this study with approximately 230 patients in the second quarter of this year. These patients are being randomized on a one-to-one basis to receive standard of care therapy with or without nearly one. The primary composite endpoint in this study is event based and consists of all cause mortality or cardiac hospitalizations. The study is designed for support full global regulatory registration. Keeping with the theme now of peripheral amyloid disease. I'd like to next highlight our pre-clinical program for ATTR amyloidosis PRX004. PRX004 is an investigational monoclonal antibody designed to specifically targeting alpha-synuclein the misfolded form of the TTR amyloid protein found in a disease noted transthyretin immediate amyloidosis or ATTR amyloidosis. Similar to AL Amyloidosis, ATTR amyloidosis is a rare progressive and sometimes fatal disease, characterized by deposition of aggregates of misfolded protein or amyloid in organs. In ATTR amyloidosis the precursor protein, transthyretin or TTR is produced primarily in the liver in its normal tetrameric form, TTR serves as a transporter for thyroxine and vitamin A. There are three types of ATTR amyloidosis, hereditary TTR with cardiomyopathy, wild-type ATTR which occurs for radically and also involve cardiomyopathy and hereditary ATTR with polyneuropathy. In the Hereditary forms of this disease the body makes a mutant form of the TTR protein. To date more than 100 reported types of TTR mutations have been reported that promote amyloid fiber formation which most commonly affect the heart and nervous system. Prothena has generated monoclonal antibodies that selectively bind to amyloid were diseased forms of the transthyretin protein. Preclinical data published in March of 2016 in the journal amyloid suggest that Prothena’s antibodies have unique biological activity that may lead to the prevention of deposition and enhancement of clearance from ATTR in patients with either wild type or hereditary TTR mediated amyloidosis. From the antibodies we generated we selected PRX004 as lead candidate and in 2016 we began producing clinical supply. We plan to initiate a clinical study in patients with ATTR amyloidosis in early 2018. Moving from amyloid diseases of the periphery, and into amyloid diseases in the CNS I'll turn to PRX002 monoclonal antibody for the potential treatment of Parkinson's disease and others synucleinopathies. PRX002 also known as RG7935 is the primary focus of our worldwide collaboration with Roche. Parkinson's is a neurodegenerative diseases that affects 7 to 10 million people worldwide making it the second most common neurodegenerative diseases after Alzheimer's. The disease is characterized by the neuronal accumulation of aggregated alpha-synuclien in the central and peripheral nervous system that result in a wide spectrum of worsening progressive motor and non-motor symptoms and a persistent throughout the disease. While the disease is most commonly known for the motor symptoms classically associated with Parkinson's disease non-motor symptoms such as loss of sense of smell, sleep disturbances or gastrointestinal matelote issues may present many years earlier. Current treatments for Parkinson's disease are primarily directed at managing the early motor symptoms of the disease, mainly through the use of levodopa and dopamine agonists. For these only addresses subset of symptoms typically related to motor impairment. Symptomatic therapies do not target the underlying cause of the diseases and as the disease progresses and dopaminergic neurons continue to be lost, these drugs lose effectiveness after leading to debilitating side effects. PRX002 has been developed as a potentially disease modifying approach to slow the progress of neurodegenerative consequences of this disease. PRX002 targeting alpha-synuclein of protein that is widely understood to be interplay involved in the onset and progression of Parkinson's diseases. Targeting alpha-synuclein has the potential to slower reduce to neurodegenerative associated with alpha-synuclein misfolding and or is cell to cell transmission. As you may recall in 2015 we reported positive results from a Phase I single ascending dose study in healthy volunteers demonstrating targeting engagement as well as the positive, safety, immunogenicity and pharmacokinetic profile for PRX002. In November of last year we reported results from the Phase IB double blind placebo controlled multiple ascending dose study in 80 patients with Parkinson's diseases. The study was designed to assess the safety tolerability, pharmacokinetics and immunogenicity of PRX002. This study demonstrated acceptable safety and tolerability across all those levels up to including 60 milligrams per kilogram the highest dose level tested with no serious or severe treatment emergent adverse events in patients treated with PRX002. In addition to achieving acceptable safety and tolerability, the study demonstrated target engagement and robust antibody penetration in the CNS. Specifically, the data demonstrated a rapid dose in time dependent reduction of free serum alpha-synuclein of up to 97%, a statistically significant result that was maintained following two additional monthly doses. In addition, we saw a robust penetration of PRX002 in the central nervous system, which exceeded our expectations based on our preclinical experience. With dose-dependent increase in PRX002 in cerebrospinal fluid and a mean concentration of 0.3% of PRX002 relative to serum across all dose levels. These data further support our belief that we can choose doses that target and saturate the aggregated pathogenic forms of alpha-synuclein in the brain for a Phase II study that will further explore the potential of PRX002 as a disease modifying treatment for Parkinson's disease, together with our partner Roche, who plan to initiate a Phase II clinical study this year. Turning now to the second area of science, where we focus. Diseases mediated by cell adhesion or cell trafficking. I'd like to highlight PRX003 for the potential treatment of inflammatory diseases, including psoriasis and psoriatic arthritis. This is our third program in clinical development. Our team is biological expertise and cell adhesion extents back to the development of Tysabri for relapsing-remitting multiple sclerosis and PRX003 builds on our expertise in this area. Our scientists working in this space and make key discoveries about the cell adhesion molecule CD146, also known as melanoma cell adhesion molecule or MCAM that is the basis of our strategy for PRX003. CD146 is cell adhesion molecule that is a specific marker for Th17 cells, which are known to play an integral role in the initiation of propagation of inflammation in auto immune conditions. Th17 cells contribute to pathogenesis via the release of multiple inflammatory cytokines and while they are best known for the secretion of interleukin-17, it has become increasingly understood that the role in pathogenesis is the result of the release of multiple cytokines including TNF alpha, interleukin-6, interferon gamma, interleukin-22 and CCL20, all of which have a well documented role in the pathogenesis of various other autoimmune diseases including psoriatic arthritis, psoriasis, rheumatoid arthritis, ankylosing spondylitis and secondary progressive multiple sclerosis. Th17 cells are defined by their expression of the cell adhesion molecule CD146. CD146 enables the mechanism whereby Th17 cells adhere to, and migrate across a blood vessel wall. PRX003 is designed to block the ability of these pathogenic Th17 cells to move out of the bloodstream and into tissue by blocking the interaction of CD146 and laminin Alpha-4, which our scientists discovered, is the binding partner on the vascular endothelium for CD146. Although Th17 cells represent fewer than 5% of T-cells, T-cells appear to be disproportionately involved in propagation of inflammation under – inflammatory diseases under pathogenic condition. Targeting the T-cell rather than any individual cytokine may provide a highly specific way to impact the pathogenic pro-inflammatory Th17 cells while leaving the vast majority of immune cells unaffected to carry out their normal function. In June of last year, we reported results from our Phase I double-blind, placebo-controlled single ascending dose study in 40 healthy volunteers. The data showed that PRX003 was safe and well tolerated to all of dose levels meeting the primary objective of the study. There were no serious adverse events, dose limiting toxicities, anti-drug antibodies or hypersensitivity reactions. In this study, we saw a dose-dependent reduction in CD146 expressions with a dose-dependent duration of response. At the highest dose, results demonstrated more than 95% neutralization of CD146 meaning nearly all binding sites were blocked by PRX003, suggesting that a single infusion of PRX003 may safely sequester Th17 cells in the blood and block CD146 mediated infiltration of Th17 cells across blood vessels into tissue. Building on the successful results, we are currently conducting a randomized double-blind placebo-controlled Phase Ib multiple ascending dose proof-of-biology study of PRX003 in patients with psoriasis. This trial is designed to further assess the safety, tolerability, pharmacokinetics and immunogenicity of PRX003 in patients with psoriasis. In this study, we will evaluate the Psoriasis Area and Severity Index known as PASI and also look to the pharmacodynamic profile in order to determine a dosing strategy for our Phase II program. As you know there are effective therapies available for psoriasis today and we realize that there is a very high bar for any future treatment in this disease to differentiate from existing therapies. If we were to observe a clearly differentiated profile in this study, we would not preclude further clinical development of psoriasis, but our assumption is that we will pursue an alternate indication with greater medical needs for our Phase II program. Therefore, in September of last year, we announced that based on meeting certain pre-specified criteria in the ongoing Phase Ib study; we intend to pursue development of PRX003 for the potential treatment of psoriatic arthritis. Psoriatic arthritis is a disease where T17 mediated biology is known to contribute to the pathology and there is a clear unmet medical need for more effective therapy. Many current treatments target a single cytokine such as TNF or IL-17 and while targeting individual cytokines is moderately effective for some patients. According to the National Psoriasis Foundation approximately 45% of patients with psoriatic arthritis are dissatisfied with their current treatment. By targeting the Th17 cells and thereby both TNF and IL-17 and also many other cytokines that play a role in the pathogenesis of this disease. We believe that PRX003 may provide a new and potentially more effective treatment for patients with psoriatic arthritis. We have recently refined our clinical development plan for PRX003 and have decided to accelerate the overall program in order to minimize the timeline to the initiation of the planned Phase II study assuming of course, that the Phase I data is permissive. We will therefore forgo an interim analysis and now expect full topline data from the Phase Ib study in patients with psoriasis sooner in the third quarter of this year. We are looking forward to sharing data from this study and believe PRX003 has a great deal of potential as a new immune cell targeting approach for psoriatic arthritis as well as a wide range of other inflammatory diseases. Finally, I'd like to highlight that this past year our management team was further strengthened with the appointment of Carol Karp as Chief Regulatory Officer. Carol who leads our regulatory quality and safety functions joins us with significant global experience across several therapeutic categories and will be invaluable to our ability to advance our clinical program towards the registration and planned commercialization of NEOD001. At this time, I'd like to turn the call over to Tran for a discussion of our financial results. Tran?