License revenues for the year ended December 31, 2023 consisted of royalties received on sales of Probuphine by Knight in Canada. License revenues for the year ended December 31, 2022 consisted primarily of an upfront license payment of approximately $50,000 related to the use of our ProNeura technology for ophthalmic use and royalties received on sales of Probuphine by Knight in Canada.
The decrease in grant revenue was primarily due to decreased activities related to the NIDA grant for the development of a Nalmefene implant and the Bill & Melinda Gates Foundation grant.
The decrease in research and development costs was primarily associated with reduced activities related to non-clinical studies required for the IND submission as part of our NIDA grant for the development of a Nalmefene implant, decreases in expenses related to initial non-clinical proof of concept studies related to our TP-2021 implant program and decreases in research and development personnel-related costs and other expenses following our December 2022 reduction in our workforce. Other research and development expenses include internal operating costs such as research and development personnel-related expenses, non-clinical and clinical product development related travel expenses, and allocation of facility and corporate costs. As a result of the risks and uncertainties inherently associated with pharmaceutical research and development activities described elsewhere in this document, we are unable to estimate the specific timing and future costs of our clinical development programs or the timing of material cash inflows, if any, from our product candidates. However, we anticipate that our research and development expenses will increase as we continue our current or any future development programs to the extent these costs are not supported through grants or partners.
We use cookies on this site to provide a more responsive and personalized service. Continuing to browse, clicking I Agree, or closing this banner indicates agreement. See our Cookie Policy for more information.