Tourmaline Bio's Pacibekitug Shows Promise in Cardiovascular Disease Treatment

Tourmaline Bio has reported encouraging results from a phase 2 clinical trial of pacibekitug, a former Pfizer antibody, paving the way for its development in cardiovascular indications. The study, known as the Tranquility trial, demonstrated the drug's potential in reducing cardiovascular disease risk in patients with chronic kidney disease.

Tranquility Trial Results

The phase 2 Tranquility trial enrolled 143 patients with elevated levels of C-reactive protein (CRP) and chronic kidney disease, who are at high risk of atherosclerotic cardiovascular disease (ASCVD). The study evaluated three dosing regimens of pacibekitug, an antibody targeting interleukin-6:

• 50 mg subcutaneous injection on day one and day 90
• 25 mg on the same schedule
• 15 mg on days one, 30, 60, 90, 120, and 150

Results showed a significant reduction in CRP levels across all treatment groups compared to placebo:

• 50 mg group: 86% average reduction
• 25 mg group: 75% average reduction
• 15 mg group: 85% average reduction
• Placebo group: 15% reduction

Sandeep Kulkarni, M.D., Tourmaline's co-founder and CEO, highlighted the significance of the quarterly dosing regimen, stating, "This is the first time that pacibekitug or any IL-6 inhibitor has been tested in a clinical trial with quarterly dosing. It is well-recognized that less frequent administration has the potential to enhance patient adherence and ultimate clinical benefit."

Safety Profile and Adverse Events

The safety profile of pacibekitug appeared favorable, with similar rates of adverse events across treatment and placebo groups:

• 54% of patients across all treatment arms experienced adverse events, compared to 56% in the placebo group
• Serious adverse events occurred in 10% of treated patients and 11% of placebo patients
• Two patients discontinued treatment due to adverse events
• One patient in the 25 mg group died from COVID-19

Future Development Plans

Based on these promising results, Tourmaline Bio is advancing pacibekitug's development in two cardiovascular indications:

1. Atherosclerotic cardiovascular disease (ASCVD): The company is designing a potential phase 3 trial, with more information to be disclosed later this year after regulatory discussions.

2. Abdominal aortic aneurysm (AAA): A phase 2 study is planned to start later this year. AAA is a condition characterized by an enlarged area of the aorta, which can lead to life-threatening bleeding if ruptured.

Additionally, Tourmaline is exploring pacibekitug's potential in thyroid eye disease, with an ongoing phase 2 trial.

Tourmaline's Strategic Positioning

Tourmaline Bio acquired pacibekitug from Pfizer in 2022, adding to its portfolio a promising asset with a history of being studied in various indications, including Crohn's disease, lupus, and rheumatoid arthritis. The company strengthened its position in 2023 through a reverse merger with Talaris Therapeutics, securing a Nasdaq listing and a $75 million private placement to advance its development programs.

As Tourmaline Bio continues to progress pacibekitug through clinical development, the pharmaceutical industry will be watching closely to see if this former Pfizer antibody can deliver on its potential in addressing significant unmet needs in cardiovascular medicine.