G&A costs include outside professional fees for legal, business development, audit and accounting services. G&A also includes cash and non-cash compensation, travel and other miscellaneous costs of our internal G&A personnel, two in total, who are wholly dedicated to G&A efforts. G&A also includes a proration of our common infrastructure costs for office space and communications. Our G&A expenses also include costs to maintain our intellectual property portfolio. Historically we have expanded our patent prosecution activities and in some cases, we have filed patent applications for non-critical strategic purposes intended to prevent others from filing similar patent claims. We continue to closely monitor our patent applications in the United States, Europe and other countries with the advice of outside legal counsel to determine if they will continue to provide strategic benefits. In cases where we believe the benefit has been realized or it becomes unnecessary due to the issuance of other patents, or for other reasons that will not affect the strength of our intellectual property portfolio, we have and will continue to abandon these patent applications in order to reduce our costs of continued prosecution or maintenance.
Critical Accounting Policies
In Item 7, “Management’s Discussion and Analysis of Financial Condition and Results of Operations,” of our Annual Report on Form 10-K for the year ended December 31, 2020, which was filed with the SEC on March 2, 2021, which we refer to as the Annual Report, we included a discussion of the most significant accounting policies and estimates used in the preparation of our financial statements. There has been no material change in the policies and estimates used in the preparation of our financial statements since the filing of our Annual Report.
Results of Operations
Comparison of the three months ended June 30, 2021 and 2020
Revenues. For the three months ended June 30, 2021 and 2020, we recorded revenue in the amount of approximately $19,000 related to the amortization of unearned license fees.
R&D Expenses. For the three months ended June 30, 2021, our R&D expenses decreased by approximately $3,000, or 86%, to $500 from $3,500 for the same period in 2020. The 2021 decrease relates to the absence of R&D reference materials in 2021 (decrease of $3,000).
G&A Expenses. For the three months ended June 30, 2021, our G&A expenses decreased by approximately $125,000, or 31%, to $276,000 from $401,000 for the same period in 2020. The changes in the G&A expenses are reflected in several areas. Decreases in professional services (decrease of $18,000), insurance (decrease of $31,000) and stock option expense (decrease of $85,000) are offset by an increase in personnel related (increase of $9,000).
Interest Expense. For the three months ended June 30, 2021, interest expense increased by approximately $29,000 which reflects the additional interest accrual related to the 2020 Notes.
Net Loss. Our Statements of Operations reflects a net loss of $339,000 for the quarter ended June 30, 2021, versus a net loss of $436,000 for the quarter ended June 30, 2020.
Comparison of the six months ended June 30, 2021 and 2020
Revenues. For the six months ended June 30, 2021, we recorded revenue in the amount of $38,000 versus $38,000 in the 2020 period. Revenue in both periods relate to the recognition of the license fees received from ReGenTree and GtreeBNT.
R&D Expenses. For the six months ended June 30, 2021, our R&D expenses decreased by approximately $3,000 or 75%, to $1,000 from $4,000 for the same period in 2020. The 2021 decrease relates to the absence of R&D reference materials in 2021 (decrease of $3,000).