DURHAM —Symmune Therapeutics, a Durham-based startup biotech focused on treating and preventing pulmonary infections and diseases by modulating the immune system, has closed on $125,000 of a $300,000 debt offering, according to a regulatory filing.

Founded in 2015, the company is developing SYM-001,  a novel composition of a well-known medical compound optimized for therapeutic activity and tolerability.

SYM-001 is being developed as a maintenance therapy for preventing  viral-induced exacerbation of COPD, including human rhinovirus, the leading cause of worsening COPD in patients.

The company’s initial funding came from a North Carolina Biotechnology Center loan.

The company website says its drug development is being driven by collaborations with top-level academic institutions and government researchs. It also has partnerships with drug manufacturing and delivery companies.

The company disclosed the debt offering in a filing with the U.S. Securities and Exchange Commission.