quarter and full year 2021 were primarily due to a decrease in the number of units of UDENYCA sold as well as a decline in net realized price due to increased competition and COVID-19 impacts.
Cost of goods sold (“COGS”) was $12.1 million and $11.7 million during the three months ended December 31, 2021 and 2020, respectively, and $57.6 million and $37.7 million for the full years 2021 and 2020, respectively. Through the first quarter of 2021, Coherus sold inventory that was manufactured and expensed prior to the approval of UDENYCA in late 2018. This inventory was depleted in the first quarter of 2021, and since then COGS fully reflects per unit acquisition cost of UDENYCA. UDENYCA COGS also includes a mid single digit royalty on net sales payable through the first half of 2024.
Research and development (“R&D”) expenses for the fourth quarter of 2021 were $50.8 million, compared to $44.6 million for the same period in 2020. The increase was mainly due to higher regulatory and development costs in support of the advancement of multiple pipeline product candidates. R&D expense for 2021 was $363.1 million compared to $142.8 million for 2020. The increase of $220.3 million was primarily due to the $136.0 million upfront license fee paid to Junshi Biosciences and also due to costs incurred in the development of YUSIMRY, toripalimab and additional presentations of UDENYCA.
Selling, general and administrative (“SG&A”) expenses were $50.1 million for the fourth quarter of 2021, compared to $37.7 million for the same period in 2020. The increase was driven primarily by increased commercialization expense to support UDENYCA sales. For the full year 2021, SG&A expenses were $169.7 million, compared to $139.1 million for the prior year. The year-over-year increase is primarily due to costs incurred in support of UDENCYA commercial activities, as well as an increase in stock-based compensation expense.
Cash and cash equivalents were $417.2 million as of December 31, 2021, compared to $541.2 million as of December 31, 2020. During 2021, Coherus used $37.4 million in operating activities and $138.4 million in investing activities, including $136.0 million in an upfront payment to Junshi Biosciences. The Company received net cash proceeds of $51.9 million from financing activities related to the issuance of common stock to Junshi Biosciences, as well as proceeds from the exercise of stock options and from purchases under the employee stock purchase plan.
Net loss for the fourth quarter of 2021 was $45.7 million, or $(0.60) per share on a diluted basis, compared to net income of $9.7 million, or $0.12 per share on a diluted basis for the same period in 2020. Net loss for 2021 was $287.1 million, or $(3.81) per share on a diluted basis, compared to net income of $132.2 million, or $1.62 per share on a diluted basis for 2020.
Non-GAAP net loss for the fourth quarter of 2021 was $35.1 million, or $(0.46) per share on a diluted basis, compared to non-GAAP income of $18.6 million, or $0.23 per share on a diluted basis for the same period in 2020. Non-GAAP net loss for 2021 was $88.5 million, or $(1.17) per share on a diluted basis, compared to non-GAAP income of $176.7 million, or $2.16 per share on a diluted basis for 2020. See “Non-GAAP Financial Measures” below for a discussion on how Coherus calculates non-GAAP net income (loss) and a reconciliation to the most directly comparable GAAP measures.
2022 Guidance
Coherus projects combined R&D and SG&A expenses in 2022 to be in the range of $415 million to $450 million, excluding a potential $25 million milestone payable upon FDA approval of the toripalimab BLA for nasopharyngeal carcinoma and the $35 million fee to exercise the option for the license to JS006, which is expected to close in the first quarter of 2022. The projected increase compared to 2021 is driven primarily by costs the Company expects to incur with the anticipated launches of two new products, toripalimab and CIMERLI, as well as manufacturing and development costs for additional presentations of UDENYCA and for FDA-approved YUSIMRY, which Coherus is planning to launch in 2023.
This financial guidance excludes the effects of any potential future strategic acquisitions, collaborations or investments, the exercise of rights or options related to collaboration programs, and any other transactions or items not yet identified or quantified. This guidance is subject to a number of risks and uncertainties. See Forward-Looking Statements described in the section below.
Conference Call Information
When: Thursday, Feb. 17, 2022, starting at 5 p.m. ET
Dial-in: (844) 452-6826 (Toll-Free U.S. and Canada) or (765) 507-2587 (International)
Conference ID: 3677018
Webcast: https://investors.coherus.com/upcoming-events