Craig Hopkinson
Analyst · Cory Kasimov with JPMorgan. Please proceed with your question
Thank you, Jim. This morning, I'll focus primarily on important updates we've made regarding our expanded NDA submission for ALKS 3831 and recent progress with our ALKS 4230 oncology program. For ALKS 3831, earlier this month, we announced that we plan to expand the NDA submission for the treatment of schizophrenia to also encompass the treatment of bipolar I disorder. This follows a constructive pre-NDA interaction with the FDA to align on this regulatory submission and the proposed pathway to support the bipolar indications for ALKS 3831. The NDA will include data from the completed ALKS 3831 ENLIGHTEN clinical program in patients with schizophrenia as well as pharmacokinetic bridging data comparing ALKS 3831 and olanzapine and data from completed drug-drug interaction studies that the FDA requested to support the bipolar filing strategy. Our team is diligently preparing the expanded file with plans to submit the NDA in the fourth quarter. These data are intended to support an indication for the treatment of adults with schizophrenia and indications for the treatment of adults with manic or mixed episodes associated with bipolar I disorder as a monotherapy or as an adjunct to lithium or valproate and for the maintenance treatment of bipolar I disorder as a monotherapy. Importantly, the proposed fixed dosage strength for ALKS 3831 include 10 mg of samidorphan co-formulated with 5 mg, 10 mg, 15 mg or 20 mg of olanzapine which reflect the spectrum of olanzapine doses commonly used to treat bipolar I disorder and schizophrenia. Both bipolar I disorder and schizophrenia are serious degenerative mental illnesses and each is estimated to affect more than 1% of the US adult population. Oral atypical antipsychotics are a mainstay of the treatment of bipolar disorder. However, patients often discontinue at a fairly high rate due to inadequate efficacy or intolerable side effects. This creates a dynamic similar to schizophrenia where patients may cycle through multiple medications and risk degenerative relapses. In practice, olanzapine has been relegated to second line treatment in bipolar disorder, largely due to weight gain and safety concerns despite established efficacy. We believe that ALKS 3831 has the potential to be a useful treatment option for adults suffering from schizophrenia and bipolar I disorder. Turning to ALKS 4230, a novel immuno-oncology candidate. The clinical development program for ALKS 4230 is progressing on multiple fronts. But let me take a step back to provide some background on the interleukin-2 biology, the molecule and the design hypothesis for ALKS 4230. At high doses, interleukin-2, which I'll now refer to as IL-2, binds to the intermediate affinity IL-2 receptors expressed on tumor-killing, CD8 positive T cells and natural killer cells. Recombinant human IL-2, known as Proleukin, is approved for patients with metastatic melanoma and renal cell carcinoma and is associated with complete and durable responses in a subset of patients. However, IL-2 more potently activates the higher affinity IL-2 receptor resulting in preferential activation and expansion of immunosuppressive regulatory T cells and poor tolerability with capillary leak syndrome, a significant concern. This toxicity profile significantly limits the use of IL-2 despite its established anti-tumor efficacy. ALKS 4230 is a stable, single polypeptide comprised of modified IL-2 and IL-2 alpha receptor chain. The novel design allows 4230 to selectively bind to intermediate affinity IL-2 receptors. This binding initiates a cascade of intracellular signaling that leads to proliferation of CD8 positive and natural killer cells. Importantly, the stable fusion design of ALKS 4230 systemically hinders its ability to bind to high affinity IL-2 receptors, which minimizes the activation of regulatory T cells. The pharmacodynamic data we have observed to date support our design and mechanism of action hypothesis. Now, I'll provide a brief overview of the status of our ARTISTRY clinical development program and then I'll provide some insight into the early efficacy signals that we are observing. The ongoing ARTISTRY-1 trial is evaluating 4230 administered intravenously daily for five consecutive days in both monotherapy and combination settings. The study is comprised of three distinct parts – monotherapy dose escalation, monotherapy expansion and a combination stage with the checkpoint inhibitor, pembrolizumab. The monotherapy dose escalation stage of ARTISTRY-1 was designed to assess the pharmacodynamic markers in all-comer patients with refractory advanced solid tumors. Data from the five completed dose escalation cohorts, spanning a dose range of 0.1 µg per kg to 6 µg per kg per day have demonstrated a dose-dependent pharmacodynamic effects of circulating natural killer cells and CD8-positive T cells and minimal and non-dose dependent effect on immunosuppressive regulatory T cells. These data are consistent with our pretest hypothesis, with effective T cell expansion in line with what you would expect to see with high-dose IL-2. The side effect profile across the completed cohorts was consistent with what one would expect to see with cytokine therapy such as fever, chills and low-grade hypertension. Importantly, no capillary leak syndrome has been observed to date. Based on these data, in June, we announced the initiation of the Phase II expansion portion of ARTISTRY-1 to evaluate the efficacy, safety and tolerability of ALKS 4230 as monotherapy in patients with renal cell carcinoma or melanoma, refractory to prior PD-1 therapies. The decisions to advance monotherapy expansion followed the identification of our recommended Phase II dose of 6 µg per kg per day. Data from this dose demonstrated the tolerability profile we set out to achieve for 4230 along with the desired lymphocyte cell expansion without corresponding Treg activation in dose escalation. In this monotherapy expansion cohort in melanoma and renal cell carcinoma, we will assess objective efficacy measures of ALKS 4230 in up to 105 patients. Following disease progression on PD-1 therapy, these patients have often very limited treatment options. These cohorts are currently enrolling in both inpatient and outpatient settings. Given the cell expansions we have observed clinically, our hypothesis remains impact that there is the potential for ALKS 4230 to have monotherapy efficacy in these initial tumor types. In parallel to the ongoing monotherapy dose escalation and expansion cohorts, we will also be steadily enrolling patients in the combination stage of ARTISTRY-1, evaluating ALKS 4230 in combination with pembrolizumab in a variety of tumor types in both inpatient and outpatient settings. Cohorts we are evaluating to PD-1 approved tumor types in both refractory and treatment naïve patients as well as tumor types that were PD unapproved at the time of enrollment including colorectal, triple-negative breast, ovarian carcinoma, soft tissue sarcomas and subjects with metastatic non-small cell lung cancer whose tumors express low or undetectable PD-L1 levels. Based on investigator feedback, we recently expanded the combination therapy portion of ARTISTRY-1 to add three cohorts evaluating patients with first-line melanoma, second line non-small cell lung cancer and second line head and neck squamous cell carcinoma. Since initiation in the fourth quarter of last year, we've enrolled approximately 20 patients in the combination therapy cohort of PD-1 unapproved tumors and are nearing completion of enrollment in this cohort. Data from these patients reviewed to date have indicated no new toxicities. Given the enrollment trends and initial signals being observed, we may expand this cohort to enroll additional subjects. In addition to ARTISTRY-1, earlier this year, we initiated ARTISTRY-2, our Phase I/II study to explore the safety, tolerability and efficacy of ALKS 4230 administered subcutaneously once weekly and once every three weeks. ARTISTRY-2 is off to solid start as we have fully enrolled the initial cohort at once weekly dose of 0.3 mg of ALKS 4230, which is intended to roughly correspond to the 3 µg per kg per day times five of the IV regimen. All seven patients from this initial cohort currently remain on therapy and initial pharmacoeconomic data from these patients have demonstrated NK and CD8 positive cell expansion, similar to what we have previously observed at the corresponding 3 µg per kg per day IV dose of 4230 with minimal activation of Tregs. I'll provide some insights into the efficacy activity we are seeing today, but I'll note that while enrollment is picking up momentum, the sample size is relatively small and we do not yet have final data or sufficient months of therapy to have a clear view into the ultimate potential of ALKS 4230. With this context in mind, we have seen initial signals of efficacy across the ARTISTRY program. When used as monotherapy treatment in the dose escalation stage of ARTISTRY-1, we also observed disease stabilization starting at the 3 µg per kg per day dose level. While we didn't expect to see much in terms of efficacy activity in this refractory all-cover population, as of the cutoff date of June 14 at 3 µg per kg and 6 µg per kg per day doses, 8 of the 14 patients who completed on-study first scans demonstrated stable disease on monotherapy treatment. Clinical benefit appears to be maintained as the majority of these eight patient continued to have stable disease upon their second scan. In the combination portion of ARTISTRY-1, we have also observed initial signs of antitumor activity. Also, as of 14 June, five of the nine patients who completed on-study first scans, demonstrated stable disease or better on their initial scans. All five patients had PD-1 unapproved tumor types. We will continue to allow these data to mature and plan to disclose additional details later this year. In ARTISTRY-2 subcutaneous study, patients receive an initial six weeks of monotherapy 4230 prior to moving into combination. While the initial six week monotherapy lead-in period is short, we have observed disease stabilization on the initial scan during the 4230 monotherapy period and look forward to following these patients as they advance into the combination stage of the study. Across the program, the feedback from the medical community thus far has been positive, with encouraging thought leader engagement at ASCO and accelerating enrollment trends across the program. We are moving into a period we expect to learn more about the profile of ALKS 4230 and look forward to providing more detailed data at a medical meeting this fall pending congress [ph] acceptance. Before I turn the call back to Rich, I'll provide a brief update on diroximel fumarate, a novel oral fumarate being developed in collaboration with Biogen for relapsing forms of multiple sclerosis. We submitted the NDA for diroximel fumarate in December of 2018 and expect regulatory action on our NDA submission in the fourth quarter of this year. We continue to expect the results of the EVOLVE-MS-2 study which is evaluating the gastrointestinal tolerability profile of diroximel fumarate head-to-head against TECFIDERA soon. Data from the EVOLVE-MS-2 are not part of our regulatory package or intended for labeling purposes. The study was designed to build upon the existing body of evidence demonstrating the differentiated GI tolerability profile of the DRF. In the meantime, we look forward to working with the agency as they complete their review of the NDA submission. Now, I'll turn the call over to Richard.