Thank you, Jennifer, and thank you to everyone for joining us on the call today. On today's call, we will provide an update on our pipeline compounds, which include our IO pipeline of Nektar IL-2, IL-15 and TLR agonist candidates and our immunology program NKTR-358. We will also review our planned upcoming milestones for these programs and provide our financial guidance for 2020. But before I discuss the advancements we made with our IO and immunology portfolio, I'd like to briefly cover some challenges we faced this year that are outside of the core focus of our pipeline. Starting with NKTR-181. As you know, we made a strategic decision last month to withdraw the NDA for NKTR-181. The NKTR-181 ADCOM was the first of several that week that were negative for the opioid class, and it became clear from these discussions that the bar for approval of any opioid compound is much higher than what was established by approvals in the past. Additionally, since that time that we submitted our NDA, the liability in the opioid class has become a significant consideration with numerous lawsuits filed against opioid manufacturers and distributors. And based upon all of these factors, we made a business decision that further investment could not be justified for medicine in this class, which would have been at the expense of sacrificing important developmental work for our immuno-oncology pipeline. As we look back at our successful development efforts for this program. I want to thank our team for their hard work, thank the patients and physicians who participated in our clinical trials, some of whom came to speak at the ADCOM. We did not take this decision lightly, but believe it is the appropriate action to take as we focus on the advancement of our IO and immunology pipeline. Secondly, as you know, we were conducting the ATTAIN study for our chemotherapy agent, ONZEALD, in advanced breast cancer patients who also have brain metastases, which compared ONZEALD to a chemo agent of choice in these patients. The ATTAIN study was being partially funded from a former partnership we had with Daiichi Sankyo. And you'll recall that the ATTAIN study was designed based upon a doubling of survival that we saw in a subset of patients from the earlier BEACON study of ONZEALD in advanced breast cancer patients with brain mets as compared to chemotherapy of physician's choice. The primary analysis of the ATTAIN study was completed late last week. And while ONZEALD performed at least as well as the physician's choice standard of care for PFS and OS, the study endpoint of improvement in overall survival was not met. As a result, we're planning no further clinical work on ONZEALD, and we're grateful to the patients and their families who participated in the ATTAIN study. With these actions behind us, our company is highly focused in the core areas of immuno-oncology and immunology, where we believe we have the potential to create transformative medicines for patients. Our IO portfolio is highly differentiated with two strong cytokine programs, IL-2 with BEMPEG and IL-15 with NTKR-255 and a small molecule TLR agonist program. This unique portfolio allows us to capture opportunities that span both solid and liquid tumors. In immunology, NKTR-358 is advancing into several clinical studies in multiple autoimmune conditions, the first of which our lupus, atopic dermatitis and psoriasis, and I'll talk more about those later on the call. Let me first start with BEMPEG, our IL-2 pathway program in T cell stimulator. Earlier this year, we announced a revised collaboration agreement with our partner, BMS, under the new joint development plan, we expanded the BMS, Nektar active Registrational Programs for the doublet of BEMPEG and NIVO from the three studies that were under way to now include seven studies in first-line and adjuvant settings, across four tumor types with more than 3,000 patients. The new Registrational Program builds upon the opportunity in melanoma, bladder cancer and renal cell carcinoma, and also adds plans for a Phase II study in first line non-small cell lung cancer. In addition to the three ongoing Registrational Trials in first-line metastatic melanoma, first-line cis-ineligible metastatic bladder cancer and first-line metastatic RCC, we've already launched a new Phase III study in muscle-invasive bladder cancer, and we are initiating a Phase III study in adjuvant melanoma. I will let Wei cover the design of these new Phase III studies in a moment. The economics of the revised agreement reflect BMS's continued commitment to the collaboration. At a high level, if you look at BMS's share of clinical costs for the new joint development plan associated with the seven studies, it is approximately $1.2 billion. There were also some enhancements to the economics for Nektar, which provide additional and accelerated near-term milestone payments. This includes a $25 million accelerated milestone payment that we received in Q1 of this year with the initiation of the MIBC study. It also includes a new $25 million milestone for Nektar at the start of the adjuvant melanoma study, which we expect will occur in Q3 of this year. In addition, the new agreement includes $75 million accelerated milestone payment at the start of the first Phase III Registrational non-small cell lung cancer study with NIVO. The rest of the economics are unchanged. BMS funds 2/3 of the development cost, Nektar contributes 1/3. Nektar books global revenues. The profit split's is 65% Nektar, 35% to BMS. We're also entitled to $650 million in total milestone payments upon the first approvals of BEMPEG in U.S., Europe and Japan, and then $260 million per each of the next three approved indications for BEMPEG. As many of you know. BMS is currently enrolling patients in our Registrational Trial in first-line metastatic melanoma, and all the investigator sites are now up and running. Last year, we obtained an FDA breakthrough therapy designation for BEMPEG plus NIVO in patients with metastatic melanoma, based on the positive data, including complete response rate from our PIVOT-02 study. The Phase III study enrolling in this setting has three endpoints, ORR, PFS and OS. The current projected earliest time line for reaching the follow-up time period needed on the number of patients required for the first interim ORR endpoint is the end of Q4 2020 this year. The PFS endpoint is projected to occur roughly six to seven months later. But as a reminder, this is event-driven, and the timing could change. For both OOR and PFS, the results will be analyzed by blinded independent radiology review. So also keep in mind that this process will affect timing for the completion of any data analysis. So the first data readout will most likely be Q1 of 2021. As we head closer, we should be able to refine this time line. As a reminder, ORR is designed as an accelerated approval endpoint. We spent only a small amount of alpha on this, and PFS is the full approval endpoint. With the breakthrough designation, the potential for the doublet in melanoma is quite promising. And as part of our amended agreement with BMS, our two companies are excited to expand our development efforts into the adjuvant melanoma setting. This essentially doubles the number of patients that could potentially benefit from this doublet in melanoma and represents a significant opportunity for BEMPEG. Given BMS has the leadership position with nivolumab across all lines of therapy in melanoma, we're pleased that BEMPEG with nivolumab has the potential to further advance the standard of care in both early and advanced stage melanoma. In bladder cancer, we are enrolling a 200-patient study in first-line cist-ineligible bladder cancer, which is intended to support a potential accelerated approval pathway in this setting. Specifically in patients with PD-L1 low expression as defined by a CPS score under 10. We expect the first potential data on the ORR endpoint from this trial in Q2 or Q3 of 2021 and to build on this opportunity in bladder cancer, we've also initiated a confirmatory Phase III study in patients with cist-ineligible muscle-invasive bladder cancer. This gives us the ability to capture the opportunity in both early and late-stage bladder cancer, expanding the potential for BEMPEG and NIVO to help even more patients. In metastatic first-line renal cell carcinoma, BMS and Nektar have chosen a comprehensive approach that positions the doublet with a TKI sparing and a TKI inclusive regimen. Our Phase III Registrational Study evaluating BEMPEG and NIVO versus a TKI and first-line RCC is now enrolling nicely, and we are on track to potentially have the first interim OS readout in the first quarter of 2022. The TKI inclusive regimen development work will start mid-year under the new BMS agreement and is designed to support a Registrational path forward in a first-line metastatic RCC study with this triplet. We will conduct a Phase I/II dose escalation and expansion study to evaluate BEMPEG plus NIVO in combination with axi in first-line RCC to establish the dose and administration schedule for future Registrational Trial. Finally, BMS and Nektar agreed on a development path for the doublet in first line non-small cell lung cancer that we believe positions BEMPEG nicely for a flexible Registrational path forward in non-small cell lung cancer. BMS will run a dose optimization and expansion study to identify the appropriate dose regimen, and BMS is paying 100% of the cost of that program. And we will continue our work evaluating pembro with BEMPEG in non-small cell lung cancer in our PROPEL trial, which is currently enrolling patients. This gives us the flexibility in the future to evaluate moving forward with either NIVO or pembro in non-small cell lung cancer. We're pleased to have the renewed agreement in place and look forward to this phase of our collaboration. This structure also removes certain exclusivity restrictions from the old agreement for a list of indications for BEMPEG and so provides us enhanced flexibility to pursue other combinations for BEMPEG. Along those lines, we're exploring the potential of BEMPEG with other checkpoint inhibitors and other mechanisms and expanding this work is a key role for us this year. In collaboration with Pfizer, we have an ongoing Phase Ib/II study in head and neck cancer and castration-resistant prostate cancer. The study will evaluate BEMPEG and nivolumab in head and neck cancer and also evaluate two triplet combinations, BEMPEG plus avelumab plus talazoparib and BEMPEG and avelumab and enzalutamide in prostate cancer. We're very excited to work with Pfizer on this because of the opportunity in these two solid tumor settings for BEMPEG, particularly in patients with PD-L1 negative tumors. We also started a study in head and neck cancer in partnership with Vaccibody. The study combines BEMPEG with their personalized vaccine approach and could pave the way for a novel treatment regimen with BEMPEG in this tumor setting. In addition, we have plans to start a study with BioXcel, combining their molecule, BEMPEG, and Pfizer, avelumab, in pancreatic cancer. As you can see, the BEMPEG program is emerging as one of the largest Registrational and development programs in immuno-oncology, and we're excited about the potential of this novel agent to combine with checkpoints and other mechanisms. Turning to our next immuno-oncology candidate, NKTR-262, our TLR7/8 agonist, our Phase I/II REVEAL study is advancing, and we recently achieved our recommended Phase II dose of NKTR-262 with BEMPEG. You'll recall that because this was a novel-novel combination, we had to evaluate staged dosing of NKTR-262 with BEMPEG and dose escalation. We've observed high levels of TLR activation in the tumor microenvironment and the dose escalation allows us to understand PK/PD and then characterize safety for NKTR-262. Our current plan is to take the recommended Phase II dose of NKTR-262 into a focused expansion in at least one tumor type, starting with 24 relapsed in refractory melanoma patients. Based upon the biology of the innate and adaptive immune system interaction, we will now evaluate simultaneous dosing of the TLR and BEMPEG to explore the combination's potential in the IO relapsed/refractory melanoma setting. The scientific community is beginning to recognize the importance of natural killer cell biology in the treatment of cancer. And as many of you know, this area of research is generating much excitement. So let me now turn to our newest clinical candidate, our IL-15 agonist program known as NKTR-255. NKTR-255 is designed to capture the full biology of the IL-15 pathway to cause both proliferation of NK cells and the expansion of CD8 memory cells, which provides us with a wide range of potential development pathways for NTKR-255. Given the product profile, we're advancing toward forward on multiple fronts with this program and JZ will provide more details on the data emerging from this program, but let me provide a high-level overview of the progress on this promising mechanism. First, we're enrolling patients into our first-in-human clinical trial of NKTR 255, which began last year. The study is evaluating NKTR 255, first as a monotherapy, and then in combination with dara or rituximab in multiple myeloma and non-Hodgkin's lymphoma, respectively. In addition, we have two research collaborations ongoing with partners who are entirely funding the research. First, Janssen is conducting preclinical studies of NKTR-255, in combination with a number of their internal oncology mechanisms. And separately, in virology, Gilead is exploring the potential of NKTR-255 in nonhuman primate studies, in combination with a number of antivirals in their portfolio. So NKTR-255 has the potential to have many applications in oncology as well as, potentially, virology, and we look forward to its progress. Moving on to NKTR-358, our Treg stimulatory program, which is partnered with Lilly. We reported significant progress with this program in 2019 last year. First the human data in healthy volunteers were reported at EULAR, and these data demonstrated the candidate's dose-dependent and selected proliferation of Treg cells. We recently completed the Phase Ib multiple ascending dose study in lupus patients, and we have submitted these data to be presented at this year's EULAR meeting. Our partner, Lilly, also recently initiated Phase Ib studies in two new autoimmune indications of psoriasis and atopic dermatitis, and these studies are ongoing and enrolling patients. Our partner, Lilly, also has plans to start a Phase II dose-ranging study in lupus in the middle of this year, and they plan to add another Phase II autoimmune indication to the development program this year. So we're very pleased with their commitment and the broad nature of this development program, which reflects the potential of this novel mechanism to treat autoimmune diseases. And with that, I'd like to turn the call over to Wei to review the Phase III study design for BEMPEG. Wei?