cohorts. We are expanding enrollment in one or more of the previously completed adult cohorts to explore dose response and support establishment of registrational trial endpoints. We anticipate establishing these registrational trial endpoints by the end of 2022. In April 2022, we announced the treatment of the first patient in the pediatric mid-dose cohort, and we expect to complete dosing of this cohort in the first half of 2022 and to initiate dosing of the pediatric high-dose cohort later in 2022.
In the third quarter of 2021, we released preliminary clinical data from the first six patients with LCA10 treated with EDIT-101 demonstrating a favorable safety profile and encouraging signals of clinical benefit. For additional information regarding these clinical data, please see Part I, “Item 1. Business—Our Gene Editing Medicine Programs—In Vivo Gene Editing Medicines - Ocular—Leber Congenital Amaurosis 10” in the Annual Report. We expect to provide a clinical update on the BRILLIANCE trial in the second half of 2022, including safety and efficacy assessments on all patients who have had at least six months of follow-up evaluations.
For our ex vivo gene-edited cell medicines, our lead program is EDIT-301, an experimental medicine to treat sickle cell disease, a severe inherited blood disease that causes premature death, and transfusion-dependent beta-thalassemia (“TDT”), the most severe form of beta-thalassemia, another inherited blood disorder characterized by severe anemia. In January 2021, the U.S. Food and Drug Administration (the “FDA”) cleared the start of enrollment and dosing of patients in the first phase of our Phase 1/2 clinical trial of EDIT-301, which we refer to as our RUBY trial, for the treatment of sickle cell disease. This study is designed to validate the safety and beneficial effects of the cell editing process. The RUBY trial is currently enrolling study participants and is on track to begin dosing in the first half of 2022 with initial clinical results expected by the end of 2022. Prior to initiating a registrational trial, in response to an FDA partial clinical hold, we will be required to develop a potency assay to ensure that the characteristics of the product released are as expected and confirmed by clinical data collected in the first patients treated. In November 2021, we filed an Investigational New Drug (“IND”) application for a Phase 1/2 clinical trial of EDIT-301 for the treatment of TDT, which was cleared by the FDA in December 2021. This trial, referred to as our EdiThal trial, is designed to assess the safety, tolerability, and preliminary efficacy of EDIT-301 for TDT. Preparations to initiate the trial are underway, and we expect to dose the first TDT patient in 2022.
In cellular therapy medicines, we continue to develop our capabilities to generate cells from induced human pluripotent stem cells to develop engineered cell medicines to treat cancer. We have advanced development of engineered iPSC-derived NK (“iNK”) cell medicines for solid tumors and generated edited NK cells from iPSCs with significantly increased anti-cancer activity. In December 2021, we declared a development candidate, referred to as EDIT-202, a highly differentiated iNK investigational medicine with double knock-in and double knock-out gene edits that are intended to enhance adaptive immune response and improve cell proliferation, cytolytic activity and persistence, as well as overcome suppressive tumor microenvironments. We are advancing EDIT-202 towards IND-enabling studies. We are also advancing alpha-beta T cell experimental medicines in collaboration with Bristol-Myers Squibb Company (“BMS”). In May 2015, we entered into a collaboration with Juno Therapeutics, Inc., a wholly-owned subsidiary of BMS (“Juno Therapeutics”), to develop novel engineered alpha-beta T cell therapies for cancer and autoimmune diseases, which was amended and restated in each of May 2018 and November 2019, at which time we also entered into a related license agreement with Juno Therapeutics, which we collectively refer to as our collaboration with BMS.
Since our inception in September 2013, our operations have focused on organizing and staffing our company, business planning, raising capital, establishing our intellectual property portfolio, assembling our core capabilities in gene editing, seeking to identify potential product candidates, and undertaking preclinical studies. Except for EDIT-101 and EDIT-301, all of our research programs are still in the preclinical or research stage of development and the risk of failure of all of our research programs is high. We have not generated any revenue from product sales. We have primarily financed our operations through various equity financings and payments received under our research collaboration with BMS and our former strategic alliance with Allergan Pharmaceuticals International Limited (together with its affiliates, “Allergan”), which was terminated in August 2020.
Since inception, we have incurred significant operating losses. Our net losses were $50.5 million and $56.7 million for the three months ended March 31, 2022 and 2021, respectively. As of March 31, 2022, we had an accumulated deficit of $908.2 million. We expect to continue to incur significant expenses and operating losses for the foreseeable future. Our net losses may fluctuate significantly from quarter to quarter and from year to year. We