began enrolling patients in the adult high-dose cohort and, following the endorsement by an independent data monitoring committee, the first of two planned pediatric cohorts. We expect to complete dosing of both the adult high-dose cohort and the pediatric mid-dose cohort in the first half of 2022. Initial clinical data from the first two cohorts is planned for presentation in September 2021.
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 beta-thalassemia, another inherited blood disorder characterized by severe anemia. In December 2020, we submitted an investigational new drug application (“IND”) to the U.S. Food and Drug Administration (“FDA”) for the initiation of a Phase 1/2 clinical trial of EDIT-301, which we refer to as our RUBY trial, for the treatment of sickle cell disease. In January 2021, the FDA cleared the start of enrollment and dosing of patients in the first phase of the trial (which is designed to validate the safety and beneficial effects of the cell editing process). In parallel, the FDA imposed a partial clinical hold and requested we 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. The RUBY trial is currently screening patients for enrollment, and we expect to begin dosing in the trial by the end of 2021. We remain on track to submit an IND for EDIT-301 for the treatment of beta-thalassemia by the end of 2021.
In cellular therapy medicines, we continue to develop our capabilities to generate cells from induced pluripotent stem cells to develop engineered cell medicines to treat cancer and are also advancing alpha-beta T cell experimental medicines. In May 2015, we entered into a collaboration with Juno Therapeutics, Inc., a wholly-owned subsidiary of Bristol-Myers Squibb Company (“Juno Therapeutics”), a leader in the emerging field of immuno-oncology, 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 them.
In March 2017, we entered into a strategic alliance and option agreement with Allergan Pharmaceuticals International Limited (together with its affiliates, “Allergan”) to discover, develop, and commercialize new gene editing medicines for a range of ocular disorders. We received an aggregate of $130.0 million in payments under this agreement, which consisted of the initial upfront payment, an option exercise payment, and a milestone payment. We and Allergan subsequently entered into a co-development and commercialization agreement under which we agreed to co-develop and equally split profits and losses for EDIT-101 in the United States. In August 2020, we and Allergan terminated the strategic alliance and option agreement and the co-development and commercialization agreement, and we assumed full rights to EDIT-101 and responsibility for conducting the clinical trial. In connection with such termination, we and Allergan entered into a termination agreement, pursuant to which we made a one-time aggregate payment of $20.0 million to Allergan.
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 Juno Therapeutics and our strategic alliance with Allergan.
Since inception, we have incurred significant operating losses. Our net losses were $112.0 million and $61.3 million for the six months ended June 30, 2021 and 2020, respectively. As of June 30, 2021, we had an accumulated deficit of $777.2 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 anticipate that our expenses will increase substantially as we continue our current research programs and our preclinical development activities; progress the clinical development of EDIT-101 for the treatment of LCA10 and EDIT-301 for the treatment of sickle cell disease; seek to identify additional research programs and additional product candidates; initiate preclinical testing and clinical trials for other product candidates we identify and develop, including EDIT-301 for the treatment of beta-thalassemia; maintain, expand, and protect our intellectual property portfolio, including reimbursing our licensors for such expenses related to the intellectual property that we in-license from such licensors; further develop our genome