Mercator’s Bullfrog Microinfusion Device Studied in DEXTERITY-AFP for Local Delivery of Anti-Inflammation Drug in DVT

October 30, 2023—The DEXTERITY-AFP trial is a phase 2, multisite trial investigating Bullfrog microinfusion device (Mercator MedSystems, Inc.) perivenous injection of dexamethasone sodium phosphate injection USP combined with contrast and at a dosage of 2 mL (6.4 mg) each 5 cm of treatment length to improve patency and post-thrombotic syndrome (PTS) 6 months after thrombus removal in symptomatic deep vein thrombosis (DVT) spanning into at least the common femoral, femoral, and/or popliteal veins.

DEXTERITY-AFP is evaluating the safety and efficacy of local drug delivery intended to reduce venous inflammation associated with DVT.

David J. Dexter, MD, presented the 6-month findings from the open-label phase of the DEXTERITY-AFP trial at The VEINS (Venous Endovascular Interventional Strategies) annual venous education symposium held by The VIVA Foundation on October 28-30 in Las Vegas, Nevada.

As summarized in The VEINS press release, the first phase of the trial enrolled 21 patients treated with dexamethasone for comparison to known historical data. In the second phase of the trial, 60 patients will be enrolled and randomized 1:1 in a dual-blinded, randomized controlled trial (RCT).

Of the 21 patients enrolled in the first phase of the trial, one patient withdrew after 1-month follow-up. Of the remaining 20 patients, 90% are male and 60% have left-sided DVT. The patients are 10.2±0.7 days post–symptom onset, and the average treatment length is 36 ± 2 cm.

Thrombus extent was categorized as 75% iliofemoral and 25% femoropopliteal.

In The VEINS presentation, Dr. Dexter reported that regarding safety, there were no device-related or drug-related serious adverse events observed. The primary efficacy endpoint— clinically relevant loss of primary patency—will be examined as combined with the RCT phase.

Of the 21 patients followed at 1 month, 19 (90.5%) had fully compressible common femoral veins and two had partially compressible common femoral veins.

Other key secondary endpoint data for the 20 patients with in-window, 6-month follow-up include the following:

• Reduction from baseline to 6 months in average Villalta score (7.3 ± 0.7 to 1.6 ± 0.4).
• Reduction from baseline to 6 months in 10-point pain score (3.2 ± 0.7 to 0.5 ± 0.2).
• Mild PTS was observed in 1 of 20 (5.0%) patients.
• No moderate to severe PTS was observed.