Scott Koenig
Analyst · H.C. Wainwright. Your line is now open
Thank you, Jim. The most important news for the company has been our recent announcement regarding the positive top line results of our pivotal Phase 3 trial in HER2+ metastatic breast cancer with margetuximab, our novel immune optimized anti-HER2 antibody, which has a Fc domain engineered to enhance engagement and activation of the immune system. Just to quickly recap those results. The SOPHIA clinical trial that the primary endpoint of prolongation of progression free survival in patients treated with a combination of margetuximab plus chemotherapy compared to trastuzumab plus chemotherapy. Patients in the margetuximab arm experience a 24% risk reduction in PFS compared to patients in the trastuzumab arm when there associated p-value of 0.033. Approximately 85% of patients in the study were carriers of the CD16A 158F allele, which has been previously associated with diminished clinical response to HERCEPTIN and other antibodies. In this pre-specified subpopulation, patients in the margetuximab arm experienced a 32% risk reduction in PFS compared to patients in the trastuzumab arm with the p-value of 0.005. The combination of margetuximab and chemotherapy demonstrated acceptable safety and tolerability, compared overall to that of trastuzumab and chemotherapy. These results offer the potential of a new treatment option for patients living with HER2+ metastatic breast cancer, a devastating disease for which there are currently no FDA approved therapies in this setting. This is the first example of an Fc-enhanced monoclonal antibody shown to be clinically superior in a Phase 3 clinical study to an antibody analog with a wild type Fc domain. And I believe these results provide important new insight regarding the importance of the immune system in mediating the clinical activity of anti-HER2 antibodies like margetuximab. Our hope is that this approach to Fc modification will not only help patients with breast cancer but potentially other types of cancer as well. We believe this is possible not only by studying margetuximab in HER2 driven cancers, including breast and gastric but also by advancing enoblituzumab in which we've incorporated the Fc mutations and for which we reported encouraging clinical data last quarter, but more on that in a few minutes. As noted in our earlier announcement, it is too early to evaluate the sequential secondary, primary endpoint overall survival, as OS events continue to crew in the study population. We planned to meet with the FDA in the first half of 2019 and I anticipate submitting a biologics licensing application to the FDA on the basis of the PFS results in the second half of 2019. We have already submitted an abstract containing previously disclosed as well as additional results to the ASCO meeting in June. In this regard, we are currently reviewing options and strategies for commercialization, assuming margetuximab received FDA approval in this indication. We are also evaluating margetuximab in a Phase 2 clinical trial in patients with HER2+ gastric or gastroesophageal junction cancer in combination with anti-PD-1 mAb. In January 2019, data demonstrating encouraging anti-tumor activity and acceptable safety and tolerability were presented at the ASCO GI symposium. In this trial, the objective response rate for this population for the HER2 IHC 3+ gastric cancer population was 32.7%. With the disease control rate, which includes partial responses and stable disease of 69.1%, median progression-free survival was 4.7 months. Following up on these results, during the first quarter of 2019, MacroGenics discussed our development plans with the FDA for a proposed registration-directed study of margetuximab in combination with MGA012 and anti-PD-1 mAb. This approach is designed to coordinately engage both innate and adaptive immunity with chemotherapy free regimen for the treatment of patients with gastric cancer in the first-line setting. We expect to initiate this study in the second half of 2019. We also plan to evaluate the merits of combining margetuximab with chemotherapy in MGA012 or MGD013 or PD-1 x LAG-3 DART in a randomized controlled study. We plan to coordinate these global efforts with our partner in Greater China, Zai Lab and hope to provide details in the coming months. Together, we believe that the Phase 3 results in metastatic HER2+ breast cancer and the Phase 2 results in HER2+ gastric cancer provides validation of our Fc optimization platform. Next, I will discuss our franchise of B7-H3 directed product candidates. Our lead program in enoblituzumab is currently in development in combination with anti-PD-1 also using an approach, where we seek to engage both the innate and adaptive immunity in a coordinated manner for cancer immunotherapy. In November 2018, encouraging data from clinical study of the combination of enoblituzumab and an anti-PD-1 mAb were presented at the Society for Immunotherapy of Cancer Annual Meeting. In the study, cohorts of patients who were naïve to anti-PD-1 therapy with either squamous cell carcinoma of the head and neck or non-small cell lung cancer had objective responses at rates that benchmarked favorably with data reported in prior studies in which patients were treated with anti-PD-1 monotherapy. The combination of enoblituzumab and an anti-PD-1 mAb demonstrated acceptable safety and tolerability in patients treated to date. Encouraged by these results, we intends to commence a Phase 2 study of enoblituzumab in combination with MGA012 in patients with squamous cell carcinoma of the head and neck beginning in the second half of 2019. I look forward to telling you more about this study as we get closer. Our second drug candidate in our B7-H3 franchise is MGD009, a bispecific DART molecule that is designed to target both B7-H3 expressed on tumor cells as well as CD3, which is expressed on normal T cells. MacroGenics is conducting a Phase 1 clinical study with MGD009 as monotherapy and in a separate study that combines MGD009 and MGA012. In December 2018, the FDA imposed the partial clinical hold on the company's Phase 1 monotherapy study of MGD009 as well as on a combination study of MGD009 and MGA012. The partial clinical hold was lifted in January of 2019. We expect to have both the monotherapy and combo studies enrolling new patients very soon. MGC018, our third B7-H3-directed molecule is an antibody-drug conjugate that target solid tumors expressing B7-H3. MGC018 is in a Phase 1 dose escalation trial, which was initiated fourth quarter of 2018. I will now turn to our PD-1-directed franchise, where we are making tremendous steps forward in advancing these programs. We have three PD-1-directed programs in the clinic, MGA012, MGD013 and MGD019. The first and most advance MGA012 is licensed to Incyte Corporation. Although, we retain the rights to develop it in combination with our pipeline programs. At the November 2018, SITC meeting, Incyte presented encouraging initial anti-tumor and safety and tolerability data in non-small cell lung cancer, cervical cancer, endometrial cancer and soft tissue sarcoma. Incyte is pursuing development of MGA012 through three monotherapy registration-directed studies with initial data anticipated in 2020, in the case of MSI-high endometrial cancer and Merkel cell carcinoma, and in 2021, in the case of anal cancer. In addition, both Incyte and MacroGenics are each studying MGA012 of combination study. I'll remind listeners that under the terms of our agreement with Incyte, MacroGenics is all eligible to receive up to $420 million in potential development and regulatory milestone and up to $330 million in potential commercial milestones. If MGA012 is approved and commercialized, MacroGenics would be eligible to receive royalties tiered from 15% to 24% of future sales of MGA012 by Incyte. Our second checkpoint molecule, MGD013, our first-in-class DART molecule that provides co-blockade of two immune checkpoint molecules expressed on T cells, PD-1 and LAG-3, for the potential treatment of a range of solid tumors and hematological malignancies. MacroGenics' Phase 1 dose expansion study in up to nine tumor types is ongoing and the company expects to present data from this study in 2019. MGD019, another checkpoint DART molecule designed to provide co-blockade of both PD-1 and CTLA-4 on T cells. MGD019 is currently enrolling patients in a Phase 1 dose escalation study. The next program, I will discuss is flotetuzumab, our bispecific, humanized DART molecule that recognizes both CD123 and CD3. In December 2018, MacroGenics presented both updated clinical data as well as gene signature data from its completed acute myeloid leukemia dose expansion cohort in two oral presentations at the 2018 American Society of Hematology Annual Meeting. In the study, flotetuzumab demonstrated anti-leukemic activity and acceptable tolerability in patients with relapsed/refractory AML, with a higher response rate observed in primary refractory patients, an extremely challenging population to treat. MacroGenics plans to enroll additional patients in this ongoing study and announce data in 2019. Servier, has development and commercialization rights outside North America, Japan, Korea and India for flotetuzumab, also known as S80880. We are collaborating with Servier on this program and under the terms of the agreement, Servier has development and commercialization rights outside North America, Japan, Korea and India for flotetuzumab. Finally, on the corporate level, we have also been busy. In November, we announced the collaboration and license agreement with Zai Lab Limited. Under the terms of this agreement, we have licensed to Zai Lab, the right to develop and commercialize margetuximab, MGD013 and an undisclosed preclinical TRIDENT binding molecule in mainland China, Hong Kong, Macau and Taiwan. Zai Lab will lead clinical development in its territory by leveraging its regulatory and clinical development expertise and broad regional network of investigators. Under our agreement with Zai Lab, we received an upfront cash payment of $25 million, less foreign withholding in January 2019 and are eligible to receive up to $140 million in potential development and regulatory-based milestone payments. In addition, Zai Lab has agreed to pay us double-digit royalties on annual net sales of the assets, which may be subject to adjustment in specified circumstances. As Jim noted earlier, we completed our follow-on offering up 6,325,000 shares of our common stock raising $118.5 million, net of underwriting discounts and commissions and estimated offering expenses. This puts MacroGenics in the strong financial position to continue to advance our multiple programs in the clinic as well as begin our preparations for the potential commercialization of margetuximab. This has been a busy and indeed transformational period from MacroGenics, as we have not only advanced number of our very exciting clinical programs, but I've also begun the process of evolving MacroGenics into a commercial pharmaceutical company, with a rich pipeline of innovative molecules in development. And now, we'd be glad to address any questions that callers may have. Operator?