The region’s hub of diagnostics and testing firms saw a slight increase in employment for the first time in four years, signaling a potential return to normal following lingering effects of the pandemic.
The sector—a collection of test makers and laboratories for infectious diseases and various cancers, specialized equipment manufacturers and testing product suppliers—saw headcount increase 1% to 4,134, according to this week’s Business Journal list, which includes 12 companies.
The companywide employee headcount grew by less than 1% to 70,494.
This follows a 3% decrease last year and a nearly 1% drop in 2024.
The declines began around 2022, after the U.S. healthcare industry rapidly expanded staff to meet the urgent need for COVID-19 tests and related supplies, leading to significant layoffs as testing demand plummeted.
Quest Diagnostics Inc. kept the top spot as the largest diagnostics firm with 2,500 employees in Orange County, unchanged from a year ago.
“Quest Diagnostics’ advanced diagnostics laboratory in San Juan Capistrano is a major source of innovation benefiting patients not only in the United States but globally,” Mark A. Machulcz, president of Quest’s West region, told the Business Journal.
In July, the New Jersey-based company, which counts 55,000 employees total, launched a new test developed at Quest’s San Juan Capistrano lab for the Oropouche virus, an emerging disease in South and Central America and the Caribbean.
Largest Increases
Only two companies on this year’s list reported year-over-year increases.
Aliso Viejo-based Ambry Genetics Corp., which was acquired by Tempus AI Inc. for $600 million in 2024, reported a 16% jump to 268 employees, making it the third largest medical diagnostics company in Orange County.
“Through offering best-in class genomic testing services, and patient-centric programs like Patient for Life, Ambry has continued to experience double-digit growth over prior year,” a spokesperson for the company told the Business Journal. “While supporting this growth, Ambry actively supports a great employee culture with programs that include hybrid and remote work opportunities.”
Ambry’s Patient for Life program has a database of clients who have sent in samples for testing and received negative or unknown results, then reanalyzes their exome data as new gene discoveries come out.
The other company reporting an increase in headcount was the precision diagnostics company MDxHealth SA. It grew 11% to 160 employees in Irvine, ranking No. 5 on the list.
MDxHealth achieved its first quarter of operating profitability in Q2 of last year and has reported 20% or more revenue growth for 17 consecutive quarters, with that dipping just slightly to 18% to $27.4 million in the third quarter.
“We’ve done it by expanding our menu through both acquisitions and what I call channel growth opportunities,” Chief Executive Michael McGarrity told the Business Journal in a previous interview.
The company also closed on its $15 million acquisition of Minneapolis-based Bio-Techne’s ExoDx business, which includes the ExoDx Prostate test. MDxHealth expects the business to contribute more than $20 million in revenue in 2026.
Alzheimer’s Test Maker to Sell Assets
Newport Beach-based Embic Corp., which seemed to be making progress on its recently FDA-approved Alzheimer’s test, has run into problems.
The company fell off this year’s list because it terminated all employees amid efforts to sell its assets, according to Chief Executive Dennis Fortier. Fortier said that he is still on the board and functioning within a consulting role.
Embic counted 12 employees as of last year.
It had developed Leqembi, a 10-minute noninvasive test that it says is 97% accurate to determine if a person is aging normally or if there are early signs of Alzheimer’s disease or other memory-impairing medical conditions.
“We are seeking to place our technology into the hands of a larger, better capitalized company with global distribution,” Fortier told the Business Journal.
Also off this year’s list: Oncology diagnostics technology firm Oncocyte Corp. recently rebranded to Insight Molecular Diagnostics Inc. (iMDx) and relocated its headquarters from Irvine to Nashville, Tennessee.
The company said that the name change and move reflect its expanded focus beyond oncology, including its strategic push into transplant medicine.
IMDx reported an estimated 13 local employees before relocating.
Research Director Desmond Celo contributed to this report.
