Pandemic,” included in our Annual Report on Form 10-K for the year ended December 31, 2021, filed with the SEC on February 28, 2022.
Financial Position
Our ability to generate product revenues sufficient to achieve profitability will depend heavily on our continued commercialization of DEXTENZA for the treatment of ocular inflammation and pain following ophthalmic surgery and for the treatment of ocular itching associated with allergic conjunctivitis, and our obtaining marketing approval for and commercializing other products with significant market potential, including OTX-TKI for the treatment of wet AMD and other retinal diseases, OTX-TIC for the treatment of open-angle glaucoma or ocular hypertension, OTX-DED for the short-term treatment of the signs and symptoms of dry eye disease, and OTX-CSI for the chronic treatment of dry eye disease. Our net loss was $18.8 million and $31.3 million for the three and six months ended June 30, 2022, respectively. Our net loss was $8.5 million and $5.4 million for the three and six months ended June 30, 2021, respectively. As of June 30, 2022, we had an accumulated deficit of $577.1 million.
Our total costs and operating expenses were $32.2 million and $63.2 million for the three and six months ended June 30, 2022 including $4.8 million and $9.6 million in non-cash stock-based compensation expense and depreciation and amortization expense, respectively. Our total costs and operating expenses were $31.9 million and $59.5 million for the three and six months ended June 30, 2021, including $4.9 million and $8.7 million in non-cash stock-based compensation expense and depreciation and amortization expense, respectively. Our operating expenses have grown as we continue to commercialize DEXTENZA following its entry into the market in July 2019; pursue the clinical development of OTX-TKI, OTX-TIC, OTX-DED, and OTX-CSI; research and develop other product candidates; and seek marketing approval for any product candidate for which we obtain favorable pivotal clinical trial results. We expect to incur substantial sales and marketing expenses in connection with the ongoing commercialization of DEXTENZA and that of any other product candidate for which we may receive approval. In addition, we will continue to incur costs associated with operating as a public company.
Although we expect to continue to generate revenue from sales of DEXTENZA, we will need to obtain substantial additional funding to support our continuing operations and the ongoing commercialization of DEXTENZA. If we are unable to raise capital through equity offerings, debt financings, government or other third-party funding, collaborations, strategic alliances, licensing arrangements, royalty agreements, and marketing and distribution arrangements when needed or on attractive terms, we could be forced to delay, reduce or eliminate our research and development programs or commercialization efforts or to relinquish valuable rights to our technologies, future revenue streams, research programs or product candidates or grant licenses on terms that may not be favorable to us.
Through June 30, 2022, we have financed our operations primarily through sales of our products, public offerings of our common stock, private placements of our convertible notes, borrowings under credit facilities and private placements of our preferred stock, which has resulted in net proceeds of $641.4 million to us.
In August 2021, we and Jefferies LLC, or Jefferies, entered into an Open Market Sale Agreement, or the 2021 Sales Agreement, under which we may offer and sell shares of our common stock having an aggregate offering price of up to $100.0 million from time to time through Jefferies, acting as agent. In connection with entering into the 2021 Sales Agreement, we and Jefferies terminated our prior Open Market Sale Agreement which we had entered into in 2019. As of August 5, 2022, we have not sold any shares of our common stock under the 2021 Sales Agreement.
DEXTENZA and all of our product candidates are designed to be medical-benefit “buy-and-bill” products with associated procedure codes. Products with these characteristics are designed to be attractive not only to physicians, optometrists, and patients but also to the sites of care that participate in utilization. We primarily derive our product revenues from the sale of DEXTENZA in the United States to a network of specialty distributors, who then sell DEXTENZA to ASCs, HOPDs, and ophthalmology and optometric offices. We also sell directly to a small population of ASCs. In addition to distribution agreements with specialty distributors, we enter into arrangements with government payors that provide for government-mandated rebates and chargebacks with respect to the purchase of DEXTENZA. In-market unit sales figures—unit sales from specialty distributors to ASCs and HOPDs—for April, May and June 2022 were 8,111, 8,828 and 10,187 units, respectively. The third month of each quarter typically reflects an increase in in-market unit sales to ASCs due to the impact of our rebate program.