Good afternoon. Before we touch on the development portfolio update, I'm going to describe the effects of COVID-19 pandemic on our business. Now despite the numerous challenges, we're fortunate that our clinical trials and research work continue to progress with modest impact on trial enrollment to date and that we continue to enjoy a strong cash position. We're still enrolling patients into a number of clinical studies that are evaluating our bispecific antibodies in oncology. And while clinical studies in oncology are still high priority for patients, their families and their physicians, the planned study initiations later this year for our two hematology programs, plamotamab, our CD20 x CD3 program, and vibecotamab, our CD123 x CD3 program, and the enrollment to our ongoing studies will likely be affected as many clinical sites have delayed starting new trials and others have postponed enrollment. This situation is very fluid and we'll continue to update as appropriate. Within the company, we've implemented a number of measures to protect the health and safety of our employees and our community. These include requiring all nonlaboratory employees to work remotely, a reduction of research lab staff density by implementing alternating shifts and by reorganizing our facility to further reduce staff density. Now a core part of our business is to complement our internal pipeline development with partnering. And we received payments from the licensing of our XmAb technologies, the clinical advance eculizumab candidates as well as royalties from sales of approved products. We're monitoring for potential impacts to this partnership revenue. On the other hand, in April, our partners Alexion and Vir Biotechnology each announced plans to initiate clinical studies evaluating antibodies and incorporate our Xtend Fc technology to treat patients with COVID-19. Alexion announced that they're initiating a Phase III trial with Ultomiris in treating patients with severe COVID-19 symptoms. And Vir, under our expanded partnership to include antibodies targeting the SARS-CoV-2 virus announced plans to initiate a Phase II study with such an antibody drug candidate. While partnerships like these certainly highlight the plug-and-play nature of the suite of Xmab Fc domains we've created, which have small changes in their structure that we designed and allow us and our partners to engineer nearly any antibody to have improved activity longer half-life or bispecific structure. This flexibility and portability to enable us to take multiple shots on goal simultaneously and generate proof-of-concept data to guide which programs we will independently advance or partner or terminate. We're focusing our R&D on the expansion use of our XmAb bispecific platform to create drug candidates that bind two more different targets simultaneously. And we're currently running six Phase I clinical studies evaluating XmAb bispecific antibody. Our plug-and-play approach to engineering enables the rapid design and simplified development of antibodies and other protein structures like cytokines. Bispecific antibodies and cytokines are a rapidly emerging area of therapeutic development, particularly in oncology. And in order to sit at the forefront of innovation in this space, we use our engineered heterodimeric Fc domain as a robust scaffold to rapidly develop new candidates that we group into three classes: T-cell engagers, tumor microenvironment activators and cytokine. The first and most advanced class is the T-cell engagers. These are tumor-targeted bispecific antibodies that contain both the tumor antigen binding domain and a cytotoxic T-cell binding domain, specifically a CD3 binding domain. These T-cell engagers, which we also call CD3 bispecifics, activate T-cells at the site of the tumor in order to potently kill malignant cells. Before we review these programs, please note that our first three CD3 bispecific programs is targeting CD123, CD20 and somatostatin receptor two have recently received their non proprietary names, vibecotamab, plamotamab, and Tidutamab, respectively. And we will be referring to these with their new names. So vibecotamab is XmAb14045, plamotamab is XmAb13676, Tidutamab and is XmAb18087. Now while we continue to dose patients in our Phase I studies of vibecotamab and plamotamab in hematologic cancers, we're planning to initiate studies of these additional studies of these programs subject to possible impacts from the COVID-19 pandemic, as I mentioned earlier. We also continue to dose patients in the Phase I study of Tidutamab and continue to expect that we will present additional data initial data from this ongoing study in neuroendocrine tumors and gastrointestinal stromal tumors in the second half of this year. Further, we've expanded our CD3 class of bispecifics by developing our XMAB 2+1 bispecific format. It uses the same heterodimeric XmAb Fc demand is in our other bispecific antibodies in cytokines, but it has two identical tumor targeting domains and one CD3 targeting domain. The two tumor targeting binding domains can both can bind together when there is more target present, a property called avidity. This enables higher selectivity for tumor antigen-expressing cells and greater flexibility in tuning the potency and hence, efficacy and tolerability of the molecule. We'll be presenting preclinical data from three internally developed XmAb 2+1 bispecific antibodies targeting solid tumors at the second session of the American Association of Cancer Research Virtual Annual Meeting in late June. The next group of bispecific antibodies are our tumor microenvironment activators. Rather than directly bridging a cytotoxic T cell to a tumor cell, our TME activators, as we call them, seek to more effectively reactivate tumor-reactive T-cells than existing therapies. These antibodies simultaneously engage multiple T cell targets, such as checkpoints or agonists. A key feature of our design is to choose individual binding affinities for each T cell target to give lower binding T cells with only one of the two targets on its surface, but they have high binding when both targets are present. This zipping up when multiple handholds are present at the same avidity property as in our 2+1 CD3 bispecifics. Now our approach reduces the need for multiple antibodies typically using combination therapy and also allows for more selective targeting of T cells that have multiple checkpoint expression, which are typically found more in the tumor microenvironment than in the periphery. Our three clinical stage TME activators target different checkpoint or co-stem combinations and all demonstrate controlling in vitro/in vivo data to support their clinical development. We're conducting Phase I studies evaluating these drug candidates in patients with advanced solid tumors. This study is evaluating XmAb22841 which targets CTLA-4 and LAG-3 and XmAb23104 which targets PD-1 and ICOs are enrolling patients in the dose escalation portion of these studies. And we've recently opened expansion cohorts in the Phase I study of XmAb20717, which targets PD-1 and CTLA-4. These cohorts are enrolling patients with advanced non-small cell lung cancer, renal cell carcinoma, prostate cancer and other cancers without approved checkpoint therapies. And the study continues to enroll patients in additional dose escalation cohorts separately. An expansion cohort for patients with the melanoma is fully enrolled. The American Society for Clinical Oncology accepted an abstract containing initial data from the dose escalation cohorts for publication in their virtual scientific program, which will appear online next Wednesday, May 13. We plan to update these data through a press release. Finally, we're developing a suite of cytokines, which are immune-signaling proteins that are built on the XmAb bispecific Fc domain and incorporate our Xtend technology. These are Fc domain and tuning the potencies enables more druggable cytokines and with potentially superior tolerability, slower receptor mediated clearance and longer half life. Our first cytokine program and the lead in our collaboration with Genentech in XmAb24306, which today they're denoting as RG6323. It's an IL-15/IL-15 receptor-alpha complex fused with our bispecific Fc domain. It targets the expansion and activation of T-cells and natural killer cells. In March, Genentech dosed the first patient in Phase I dose escalation and expansion study of XmAb24306 in a single-agent and in combination with atezolizumab, their anti-PD-L1 antibody. The study is enrolling patients with locally advanced or metastatic solid tumors. And I recall that we can perform our own clinical studies with both our own pipeline assets and non-Genentech agents within this collaboration, subject to some conditions. We look forward to planning a number of these combination studies pending completion of the initial dose escalation study. We look forward to keeping you informed about all of our clinical programs as they progress. Now I'll switch to reviewing some updates from our partnerships. While we have 10 ongoing partnerships for Xmab technology, which have resulted so far in one marketed product, one now under review for marketing approval, seven clinical candidates and more in earlier stages of development, we are only going to update on three today before proceeding to financials. MorphoSys in 2010 licensed from us tafasitamab, which was previously known as MOR208, and before that, XMAB5574. It's an anti-CD19 antibody that we designed and initially developed incorporating our cytotoxic Fc domain for high Fc for high ADCC function. In late February, the FDA accepted MorphoSys' BLA submission for treating patients with diffuse large B-cell lymphoma, for which they received a $12.5 million milestone payment. Their submission was granted priority review and received a PDUFA goal date of August 30, 2020. We're eligible for additional milestones royalties on sales on sales in the high-single to low double-digit percentage. We've also entered into research collaborations that include the creation of a novel XmAb biospecific antibody to be advanced by partners. For example, AMG 509, Amgen's STEAP1 x CD3, 2+1 bispecific antibody, developed under our collaboration with them. Amgen is developing AMG 509 for patients with prostate cancer and ewing sarcoma. Preclinical data presented during session one of the AACR virtual annual meeting in April. Amgen is now recruiting patients in a Phase I study of the AMG 509 in patients with metastatic castration-resistant prostate cancer or prostate cancer. Now last program is, in January, we entered into a technology license agreement with Gilead who was accessing our extended half-life and cytotoxic Fc technologies for developing and commercializing elipovimab, their first-in-class broadly neutralizing anti-HIV antibody in Phase I clinical development as well as up the three additional anti-HIV antibodies. At this time, Gilead has exercised all three options for the additional antibodies. And in total, we received $13.5 million under the agreement. Now our partnership with Gilead and the expansion of our partnership with Vir in COVID-19, both highlight our strategy to selectively license access to our XmAb technologies producing and developing antibodies with improved properties and shows broad applicability in areas such as viral infectious disease. And the plug-and-play nature of our XmAb technologies enable us enables our partners to advance their programs needing very little resources or effort from us. Now with that, I'm going to turn the call over to John Kuch to review our first quarter 2020 financials.