Starting with our Balance Sheet review, cash balances at June 30 were $19.5 million, as compared to $9.9 million on Dec 31, 2020, and working capital was $19.3 million as compared to $9.4 million at the end of 2020.
The increase in our cash balances is due primarily to our February offering, with net proceeds to us of $9.4 million. During the first quarter, we also received $3.2 million from the exercise of the warrants issued in connection with our stock offering last September. As a quick recap, those warrants are publicly traded under the symbol GOVXW. They have a $5.00 exercise price and expire in September 2025. After these recent exercises, there are 1.9 million of these warrants remaining outstanding which, if exercised in full, could bring in an additional $9.3 million.
Turning attention now to the Income Statement, I’ll focus mostly on the comparative figures for the 6-month periods of 2021 vs 2020. Grant and collaboration revenues were $190,000 during 2021 vs $1.2 million in 2020. The 2021 period revenues relate entirely to our grant from the NIH supporting our COVID-19 vaccine, while the 2020 amount includes revenues from our grant from the U.S. Army supporting our Lassa Fever vaccine program, and also to our collaboration with Leidos for work on a malaria vaccine.
Research and development expenses were $1.4 million in 2021 vs $1.3 million in 2020, with the increase associated with our COVID-19 vaccine program, manufacturing process development, and a generally higher level of activity.
General and administrative expenses were $1.8 million in 2021 vs $930,000 in 2020. A large portion of the increase here relates to the annual Delaware franchise tax, which is based on our capitalization and was minimal in 2020. Other increases in patent costs, legal fees, consulting fees, and personnel costs are generally associated with preparing the organization for a higher activity level following our capital raises.
During the second quarter, we reported a $172,000 gain on extinguishment of debt, associated with the forgiveness of the PPP loan we received in early 2020. Overall net loss for 2021 was $2.9 million (or $0.49 per share) vs $1.1 million in 2020 (or $2.27 per share). The variance in the per share amounts is in part due to the dilutive effect of the September 2020 and February 2021 stock offerings.
Our net cash flow from operating activities during 2021 was nearly the same as our net loss for the quarter at $2.9 million. In general, we expect our current cash resources to sustain our operating plans at least through mid-2023. Our cash burn rate for core operations (personnel, facilities, lab operations, etc.) is less than $5M annually, but our incremental program spending will increase as we progress to clinical trials.
And finally, a summary of our capital structure. We currently have 6.3 million common shares outstanding and 1.9 million of the GOVXW warrants outstanding (exercisable at $5.00 per share). There are an additional 1.5 million stock options and warrants with an average exercise price of $4.26.
GeoVax Labs, Inc. is a clinical-stage biotechnology company developing human vaccines against infectious diseases and cancer using novel patented platforms. GeoVax’s Modified Vaccinia Ankara-Virus Like Particle (MVA-VLP) based vaccine platform utilizes MVA, a large virus capable of carrying several vaccine antigens, that expresses proteins that assemble into VLP immunogens in the person receiving the vaccine. The production of VLP in the person being vaccinated can mimic virus production in a natural infection, stimulating both the humoral and cellular arms of the immune system to recognize, prevent, and control the target infection. The MVA-VLP derived vaccines can elicit durable immune responses in the host similar to a live-attenuated virus, while providing the safety characteristics of a replication-defective vector.
GeoVax’s MVA-VLP development programs are focused on preventive vaccines against COVID-19, HIV, Zika Virus, and hemorrhagic fever viruses (Ebola, Sudan, Marburg, and Lassa), as well as therapeutic vaccines against multiple cancers. The Company has designed a preventive HIV vaccine candidate to fight against the subtype of HIV prevalent in the commercial markets of the Americas, Western Europe, Japan, and Australia; human clinical trials for this program are managed by the HIV Vaccine Trials Network (HVTN) with the support of the National Institutes of Health (NIH). GeoVax’s HIV vaccine is also part of a collaborative effort toward a functional cure for HIV.
This release and the related conference call contain forward-looking statements regarding GeoVax’s business plans and financial results. The words “believe,” “may,” “estimate,” “continue,” “anticipate,” “intend,” “should,” “plan,” “could,” “target,” “potential,” “is likely,” “will,” “expect” and similar expressions, as they relate to us, are intended to identify forward-looking statements. We have based these forward-looking statements largely on our current expectations and projections about future events and financial trends that we believe may affect our financial condition, results of operations, business strategy and financial needs. Actual results may differ materially from those included in these statements due to a variety of factors, including whether: GeoVax and its collaborators are able to complete their work within the expected timeframes, GeoVax is able to obtain the patent protection sought, GeoVax’s COVID-19 vaccines can provoke responses to multiple COVID-19 antigens, and those vaccines can be used effectively as a primary or booster to other COVID-19 vaccines, GeoVax’s viral vector technology adequately amplifies immune responses to cancer antigens, GeoVax can develop and manufacture its vaccines with the desired characteristics in a timely manner, GeoVax’s vaccines will be safe for human use, GeoVax’s vaccines will effectively prevent targeted infections in humans, GeoVax’s vaccines will receive regulatory approvals necessary to be licensed and marketed, GeoVax raises required capital to complete vaccine development, there is development of competitive products that may be more effective or easier to use than GeoVax’s products, GeoVax will be able to enter into favorable manufacturing and distribution agreements, the impact of the COVID-19 pandemic continues, and other factors, over which GeoVax has no control. Further information on our risk factors is contained in our registration statement on Form S-3 and the periodic reports on Form 10-Q and Form 10-K that we have filed and will file with the SEC. Any forward-looking statement made by us herein speaks only as of the date on which it is made. Factors or events that could cause our actual results to differ may emerge from time to time, and it is not possible for us to predict all of them. We undertake no obligation to publicly update any forward-looking statement, whether as a result of new information, future developments or otherwise, except as may be required by law. Contact: GeoVax Labs, Inc. email@example.com 678-384-7220
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