Thanks, Chris and good afternoon, everyone. Thanks for joining us for an update on CytomX continued progress. The promise of masking and conditional activation strategies to improve the therapeutic window for potent biologics like ADCs, T-cell engagers and cytokines continues to be an important and exciting frontier in cancer R&D and our leadership in this field at CytomX derives from more than a decade of innovation with the Probody therapeutic platform. Our foundational clinical work with the Probody platform has achieved many firsts in demonstrating how marketing strategies could be effective in cancer patients, and we have opened a broad field in which progress continues to accelerate. The CytomX team is highly focused on delivering on the promise of conditional activation for the benefit of patients. We're currently advancing a generation of product candidates that span multiple modalities, leveraging validated oncology targets, potent effective mechanisms and tailored masking strategies. Each of our candidates is designed to address large commercial markets and major unmet medical need in cancer. We've had a highly productive start to 2024. We remain on track for initial CX-904 Phase 1a dose escalation data in the second half of this year, and we are busy launching Phase 1 clinical trials for our newest therapeutic candidates CX-2051 and CX-801 with initial Phase 1a data anticipated in 2025. Let me now provide additional context and detail for our lead programs. I'll start with our -- with CX-904, our Probody T-cell engager targeting EGFR and CD3. T-cell engaging bispecific antibodies have enormous potential for the treatment of cancer and first demonstrated meaningful clinical benefit in hematologic malignancies. Looking across the T-cell engager landscape for solid tumors is taken time to see meaningful clinical results, but we're now starting to see important breakthroughs generating great excitement. Successes include Immunocore Tebentafusp in Uveal Melanoma, the first approved T-cell engager for solid tumors, and more recently Amgen's Tarlatamab targeting DLL3, which has demonstrated impressive results in small cell lung cancer. The development of these and other programs has not only provided long awaited proof-of-concept, but this important work has also helped to increasingly define a roadmap and key considerations for how to optimally develop this emerging class of potent therapies including optimization of dosing paradigms. However, for this modality to fully breakthrough in solid tumors, there are still significant challenges to overcome. T-cell engages bring very high potency, and this potency can lead to toxicities in normal tissues where the tumor oxygen of interest may also be present. In fact, this is very often the case, a normal tissue target expression is widely acknowledged to be a limitation on the development of T-cell engages for solid tumors. Furthermore, another well acknowledged limitation for T-cell engages is cytokine release syndrome resulting from systemic binding to CD3 on T-cells. At CytomX, we have a broad-based program focused on masking T-cell engagers to decrease tumor antigen binding in normal tissues and CD3 binding in the periphery, thereby improving therapeutic index. We are working with partners Amgen, Astellas, Regeneron, and Bristol-Myers Squibb in this exciting space. Our lead program is CX-904 that targets the tumor antigen EGFR and CD3 on T-cell. CX-904 is designed to address the principal challenges of developing an EGFR CD3 T-cell engager with the goal of delivering anti-tumor activity at tolerable systemic doses. This program is partnered with Amgen and a global co-development collaboration. The market opportunity for CX-904 is broad. There are hundreds of thousands of EGFR positive patients with metastatic tumors across a wide range of cancer types that could potentially be addressed by this therapy. CytomX is currently conducting an ongoing Phase 1a study in late-stage unselected patients with advanced solid tumors generally known to have EGFR expression. Our principal goal for this Phase 1a study is to evaluate safety and to identify doses and schedules for detailed evaluation in specific EGFR positive cancer types in Phase 1b. More specifically on safety, we're looking to keep CRS and the typical EGFR mediated toxicities at manageable levels in order to achieve doses in the predicted therapeutically active range. The selection of Phase 1b tumor types will be driven by a combination of factors including observations from Phase 1a, unmet medical need and commercial potential, including fit with our partners' strategic interests. We are making steady progress in the clinic, having now advanced through multiple dose cohorts at above dose levels that would be expected to be tolerated with an unmasked EGFR T-cell engager. In late 2023, we also began to backfill certain dose levels to more fully explore the profile of this drug candidate. We expect to share initial Phase 1a dose escalation data in the second half of 2024 with our partner Amgen, and also to present these data in an appropriate setting externally. These data will inform a potential decision to initiate Phase 1b in 2025. Moving now to our continued work in the antibody drug conjugate space. There has been tremendous progress in ADCs in the past few years and the impact for patients has driven significant strategic interest in this field. CX-2025 is our first-in-class EpCAM-directed Probody ADC. Our IND application for CX-2051 was cleared by the FDA in January, clinical study start-up activities are in progress and we expect to initiate Phase 1 dose escalation in solid tumors generally known to have EpCAM expression including colorectal cancer in the near-term. EpCAM is a high potential oncology target due to its high cell surface expression in many cancer types. Indeed, EpCAM was one of the first tumor actions to be characterized more than three decades ago and it has since been implicated in many roles in cancer progression. Anti-EpCAM therapeutic strategies have shown potent anticancer activity in pre-clinical models and this has been translated into clinical activity, but to-date, clinical success has been limited to local administration because EpCAM is present in so many normal epithelial tissues. Efforts to generate systemically administered anti-EpCAM therapeutics have not been successful to-date due to toxicities in epithelial tissues, including the GI tract. Our innovative drug candidate, CX-2051, and is tailored to optimize the therapeutic index for EpCAM-expressing epithelial cancers by marking the antibody to reduce binding in normal tissues but to allow activation in tumor tissue. We have armed the antibody with a cytotoxic payload based on camptothecin, a topoisomerase I inhibitor, a class of drug that has shown potent clinical anticancer activity in the ADC context for multiple targets, leading to dramatic advances for patients. CX-2051 has demonstrated a wide predicted therapeutic index and strong preclinical activity and tolerability in multiple preclinical models, including colorectal cancer. Like EGFR I discussed previously, CX-2051 could also potentially address a large patient population as EpCAM is highly expressed across many indications, including colorectal, gastric, endometrial and ovarian cancers. Our Phase I trial will follow an adaptive design and is intended to demonstrate rapid clinical proof of concept to inform a potential decision to move into dose expansion studies in 2025. We're really excited to see what this unique and first-in-class ADC can do for patients. Turning now to CX-801, our duly masked conditionally activated interferon alpha-2b, which we believe has the potential to become a cornerstone of combination immunotherapy for a wide range of tumor types. The IND for CX-801 was cleared by the FDA in January, and we expect to initiate Phase I dose escalation in solid tumors, including melanoma, renal cancer and head and neck squamous cell carcinoma in the first half of 2024. Interferon alpha is a powerful cytokine with the ability to potently drive tumor antigen presentation and activate antitumor immunity. It has demonstrated clinical activity and gained regulatory approval many years ago in multiple cancer types, including melanoma, renal cancer and bladder cancer. However, interferon therapy is well known to be associated with significant systemic side effects and its use has been superseded by checkpoint inhibitors and other therapeutic approaches. It's also been shown that interferon could potentiate the clinical effects of PD-1 in metastatic melanoma. But again, this approach has been limited by systemic toxicities. Interferon therapy has recently returned to focus with Ferring Pharmaceuticals' approval in 2022 of Adstiladrin, an interferon alpha-2b encoding gene therapy indicated for the treatment of localized BCG nonresponsive non-muscle invasive bladder cancer, reaffirming that this potent cytokine could indeed achieve robust antitumor responses in patients. Based on the preclinical profile of CX-801 as well as prior clinical experience with interferon therapies, we see 801 as a potential new centerpiece of combination cancer immunotherapy. Our preclinical data most recently presented at 60, 2023 demonstrates synergy for our masked interferon alpha with PD-1 inhibition, both in terms of antitumor activity, and in activation of the tumor inflammatory microenvironment. Moreover, we've also shown that systemic activity of our masked interferon is significantly reduced and overall tolerability is markedly improved compared to the unmasked cytokine in animal models. We anticipate that the opportunity for CX-801 will be in combination with checkpoint inhibition, where it could serve as a potent immune modulator to both increase the frequency and durability of responses in IO sensitive tumors potentially to establish or restore efficacy in IO resistant or cold tumors. Our Phase I dose escalation trial being initiated in the first half 2024 will utilize an adaptive design to evaluate safety and signs of clinical activity for 801 monotherapy and advance rapidly to combination with checkpoint inhibition. Before moving to financials, I'd like to provide updates on our partnerships, and starting with an update on our long-standing collaboration with Bristol-Myers Squibb. We were informed on March 6 of BMS's intention to discontinue BMS-986288, the CTLA-4 program. This unexpected decision followed a broad internal portfolio review at BMS. We continue to work with BMS to gain more visibility on the data from this program and the factors that led to this decision. Moving forward, the BMS collaboration continues to be very active and will now focus primarily in the field of T-cell engagers, where, together, we have initiated several new programs over the last 2 years. Notably, this shift in focus within the BMS alliance now means that the majority of our partner programs are now focused on T-cell engagers, reflecting strong strategic interest in this area and showing that this modality is emerging as a key application of masking and conditional activation. Continuing the T-cell engager theme, given our ongoing progress with enrollment of the CX-904 Phase 1a study, I'd like to outline some of the key terms of our strategic alliance with Amgen. Under the terms of our agreement, CytomX and Amgen are co-developing CX-904. CytomX is responsible for early-stage development and Amgen will be responsible for late-stage development, with the transition occurring after completion of Phase 1b by CytomX. Within the CX-904 agreement, CytomX has an option to participate financially in the global co-development of CX-904 with Amgen. If we exercise our co-development option, we opt in to a significant U.S. profit share and we are eligible for up to $460 million in development, regulatory and commercial milestone payments and ex U.S. royalties in the low double-digit to mid-teen percentage. We see this collaboration as having substantial potential to build long-term value for CytomX, and we look forward to making additional progress with our partner on this program. Moving now to our other drug discovery stage partnerships. We continue to make progress in our alliances, including with our newest partners, Regeneron and Moderna. Across our alliances, we have more than a dozen active discovery programs. CytomX holds significant commercial rights on a number of these assets, and we have multiple near- and long-term milestones that we're working towards. Chris will review in a few moments the financial benefits that continue to accrue to us from our partnerships as we run the company in a very capital efficient way. With that, I'll hand over to Chris to provide a financial update.