Petaluma pharmaceuticals startup Collidion Inc. on Aug. 8 said it is acquiring most of San Diego-based CalAsia Pharmaceuticals, Inc., dba Plex Pharmaceuticals, which is developing treatments for Parkinson’s disease, brain cancer and cataracts.

The definitive agreement is said to include 80 percent equity in Plex in exchange for an undisclosed amount of cash and contributing a novel drug asset under development. Collidion would provide management and operational support as Plex continues drug discovery. Plex’s efforts have received nearly $3 million in several grants from the National Institutes of Health and the Michael J. Fox Foundation for Parkinson’s Research.

This is the first acquisition for 2-year-old Collidion. Plex was started in 2009.

“This acquisition provides Plex with a strong financial footing and enables further development of our proprietary pipeline of therapeutic candidates,” said G. Sridhar Prasad, Ph.D., Plex’s president and chief scientific officer, in a statement. “Plex’s drug portfolio is led by a combination treatment approach for glioblastoma, as well as development candidates for Parkinson’s disease and cataracts. This transaction further validates and represents a tremendous opportunity for us to advance our programs into pre-clinical and clinical development, as well as invest in further development of our drug candidates for additional indications.”

Plex has developed a novel co-drug molecule to treat glioblastoma, one of the deadliest forms of cancer. The market for treatment of this condition is expected to reach $3.3 billion by 2024, according to a January 2016 report by GlobalData, cited by Collidion.

A combination of aggressive treatments is traditionally used to target the tumor site. Plex’s two drug molecules are delivered in a single conjugate and later released as two single-agents, each targeting the tumor sites. Plex’s pre-clinical data demonstrates a greater level of efficacy when the combined drug molecules target the same glioblastoma tumor models, over the separate use of each drug molecule, Collidion said.

The first molecule used in Plex’s formulation has been approved by the Food and Drug Administration, while the second component is currently undergoing clinical investigation for treatment of multiple systemic cancers. Management believes that the combined molecule has the potential to be reviewed and ultimately receive an orphan drug status by the FDA for glioblastoma treatment.

“Collidion’s acquisition of Plex reinforces our commitment to innovation and cross-collaboration,” said Hoji Alimi, Collidion chairman and CEO. He started the company in Santa Rosa in 2015 and relocated it to Petaluma last year.

Alimi is a serial North Bay medical technology entrepreneur. He had led Santa Rosa-based Ruthigen in 2013 as it spun off from Oculus Innovative Sciences, a Petaluma-based wound-care products maker. Ruthigen was acquired in 2015. A Sonoma State University alumnus, Alimi created Oculus as MicroMed Laboratories in April 1999, changing the name to Oculus in 2001 then taking the company public in 2007.

Plex has a “promising” approach to Parkinson’s disease, Collidion said. It progressively degrades the nervous system and typically affects people over age 60. Symptoms include tremors, trembling in the limbs and face, stiffness of both limbs and body trunk, slowness in movement, and impaired balance. Patients gradually experience difficulty in walking, speaking or completing simple daily tasks.

Collidion said it is committed to accelerating in vivo proof of concept for this condition, which has a global market estimated to reach $3.2 billion in 2021, based on a February 2016 report by GBI Research.

Plex is developing a topical drug to treat or delay the progression of cataracts, a progressive medical condition that clouds the lens of an eye, impairing vision. The drug, if approved, may cut into the global cataracts surgical market, which is estimated to reach $4.7 billion by 2020, based on a Global Industry Analysts, Inc., report in January 2015.

Plex’s cataracts program is currently being supported through NIH grant funding.

Prasad will remain director and chief scientific officer of Plex. Alimi will be appointed chairman and CEO; William H. Watson III, Collidion’s vice president of global sales and business development, as vice president of business development of Plex; and Sameer Harish, Collidion’s director of finance, in the same role at Plex.

Plex’s board will have Alimi, Prasad, Watson and two remaining seats. Plex will be expanding its Scientific Advisory Board, led by Allan Rubenstein.

“The Plex acquisition is a major milestone for Collidion,” Watson said. “By adding Plex’s robust pipeline of novel drug leads to our three anti-infective platforms, we are setting the stage towards becoming a significant player in the global market.”

Collidion’s solutions include several antimicrobial platforms that can have applications in human and animal medicines, wound care, surface disinfection, and improved safety for the food supply chain.

“Plex has played a key role in developing several of our anti-infective platforms,” Watson said. “Their work has led to the development of a robust anti-infective technology, with results confirming an 8-log spore reduction in 30-minutes in presence of serum. Our vision is to commercialize this platform for rapid and safe sterilization and disinfection of medical devices including, but not limited to heart lung bypass machine, kidney dialysis machine, and many others. We intend for this antimicrobial platform to become the leading disinfection solution for combating infectious disease even in presence of serum that are generally found on reusable medical devices.”

Legal advisers in the deal were FitzGerald Yap Kreditor LLP for Collidion and Pokala Law for Plex.