During the first 18 months of the trial, we have made progress toward our objectives. The project goals have not been modified.
Our overall objective is to determine a clinically optimal dose and estimate the efficacy of propranolol in dogs with hemangiosarcoma when given as an adjunct to chemotherapy. Specifically:
Objective 1: We will confirm the tolerability and estimate the clinical benefit of propranolol in combination with doxorubicin.
Objective 2: We will assess levels of propranolol in the bloodstream after long-term administration to dogs with hemangiosarcoma to determine if there is a correlation between drug levels in blood and treatment effect. We will also determine if propranolol alters the blood levels (exposure) of doxorubicin in dogs receiving propranolol and compare these levels to those found in the published literature for dogs receiving doxorubicin. Collection of these data will allow us to better understand how these drugs may be working together.
We opened the trial on July 1, 2019. As of December 31, 2020, we have enrolled eight dogs in the study and no dose limiting toxicities have been observed. Based on these results, we are continuing to enroll dogs at the highest dose of propranolol (1.3 mg/kg) being tested.
Propranolol and doxorubicin levels in the blood from six of the dogs have been analyzed, and analysis of samples from the seventh and eighth dogs is pending.
The study was been delayed by approximately four months due to the COVID-19 pandemic. Enrollment was halted at all three study sites (University of Minnesota, University of Pennsylvania, Purdue University) in early to mid-March. Enrollment resumed at all three sites in late June/early July. Our plans are to continue to screen and enroll dogs into the study with the goal of enrolling another 8- 10 dogs within the next 6-9 months. We also plan to complete the initial analysis of drug levels in the blood samples