Xencor Inc., a biotechnology company that produces monoclonal antibodies to combat cancer and other life-threatening diseases, reported a $12 million loss in the fourth quarter and an overall loss of $49 million last year.

The Monrovia-based company announced in a Feb. 28 filing with the U.S. Securities and Exchange Commission it had lost $11.8 million (or 25 cents a share) for the three months ended Dec. 31, 2017, compared with $9.1 million (or 21 cents a share), for the same period a year earlier.

The 21-year-old firm reported net loss last year of $48.9 million (or $1.05 a share), compared to $23.6 million (or 56 cents a share) in 2016. Revenues for 2017 were $35.7, compared with $87.5 million in 2016.

Shares of Xencor fell 4.9 percent to $29.13 at the close of trading March 1, after rising 21.0 percent for the week ended Feb. 28. Its market cap was $1.37 billion.

Xencor attributed its higher fourth-quarter loss to greater spending on research and development. It said the greater loss in 2017 was mostly because of increased expenses last year. In addition, a collaboration with Novartis Inc. in 2016 had resulted in proceeds of $150 million.

The clinical-state biopharmaceutical company develops engineered monoclonal antibodies to treat autoimmune disease, asthma, cancer and more. Its year-end report highlighted progress in clinical trials and pending data for various drugs.

It said eight pharmaceutical companies and the National Institutes of Health were advancing novel drug candidates either discovered at Xencor or were based on its proprietary technology.

Monoclonal antibodies are laboratory-produced molecules engineered to serve as substitute antibodies that can restore, enhance or mimic the immune system’s attack on cancer cells, according to the Mayo Clinic.

The global market for monoclonal antibodies, now widely used in medicine and biologic science, topped $100 billion in 2017, according to a Feb. 21 report by Kalorama Information, a division of MarketResearch.com.

Health business reporter Dana Bartholomew can be reached at dbartholomew@labusinessjournal.com. Follow him on Twitter @_DanaBart.