Update on clinical trial for hemangiosarcoma treatment from Dr. Dickerson.
During the 6 months that the project has been active, we have made progress toward our objectives. Based on our experiences during this time, we have made some minor adjustments to the day-to-day running of the clinical trial and reporting of results. 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.
Objective 1: We will confirm the tolerability and estimate the clinical benefit of propranolol in combination with doxorubicin.
Objective 2: We will assess the circulating drug levels of propranolol after long-term administration to dogs with hemangiosarcoma to determine if there is a correlation between plasma drug concentration and treatment effect. We will also determine if propranolol alters the plasma 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, and as of December 15, 2019, we have screened 10 dogs and enrolled three dogs in the study. Dogs that were not enrolled did not meet enrollment criteria (e.g. evidence of metastatic disease) or the owner declined enrollment. The first dog was enrolled in midSeptember, the second in October, and the third dog in November.
Overall, propranolol has been well-tolerated by all of the dogs; no dose limiting toxicities were noted in the three dogs enrolled. One dog did have gastrointestinal upset that was attributed to the chemotherapy (doxorubicin) used in the study. Propranolol and doxorubicin levels in the plasma from two dogs has been analyzed, and analysis of samples from the third dog is pending. Our plans are to continue to screen and enroll dogs in the study with the goal of enrolling another 8-10 dogs within the next 6 months. We also plan to complete the initial analysis of drug levels in the plasma samples during this time.