Toward the first vaccine for a common infection

COLOGNE, Germany—The first vaccine for respiratory syncytial virus (RSV), a common infection that hospitalizes hundreds of thousands of Americans each year, may be on the horizon. CEVEC Pharmaceuticals announced success using CAP cells, an immortalized cell line, to produce RSV in very high titers in a form that is especially promising for use as a vaccine. CEVEC’s evaluation study of the RSV production system was conducted in partnership with Paragon Bioservices, a biopharmaceutical contract manufacturer based in Baltimore, Md.

Currently there is no vaccine to prevent RSV, which infects the lungs and breathing passages of most infants before age 1, and virtually everyone by age 2, according to the U.S. Centers for Disease Control and Prevention (CDC). It is the most common cause of lower respiratory tract infections among young children worldwide. Most healthy adults recover within two weeks, but the infection is often severe in children and older adults, and in many cases leads to bronchiolitis or pneumonia. The CDC estimates that RSV causes the hospitalization of 132,000 to 172,000 children younger than 5 each year in the United States and 177,000 hospitalizations and 14,000 deaths among adults older than 65.

Many common childhood diseases can now be prevented by early vaccination, but efforts to produce a RSV vaccine have so far failed due to the lack of a effective expression system. The airway epithelial cells that are the natural target for the infection in humans are not well-suited for production of a vaccine because they are primary cells. Other cell lines that have been evaluated for production of a vaccine were deemed too highly tumorigenic.

CEVEC, which is focused on the development of protein and vaccine expression systems, saw an opportunity to use its CAP cells, which are derived from primary human amniocytes, as a production system for the vaccine that would succeed where others had fallen short. CAP cells grow in serum-free suspension culture, allowing for stable production of proteins and vaccines. “CAP cells can do things that traditional cell lines that have been used for vaccine production cannot do because traditional cells are not human cells,” Gary Boch, CEVEC’s vice president of business development, tells DDNews. “Our cells are human cells, so when they express protein the result is a human protein.”

The RSV that was produced by CAP cells in CEVEC’s evaluation study was promising for two reasons. First, the RSV showed a high-level of functional G-protein, which is expected to result in a high-quality vaccine. Other production systems were unable to produce RSV with this quality. Another positive outcome of the study was the very high titers in which the RSV was produced. “Again CAP cells prove their enormous potential and significant advantages over many currently used production systems for vaccines,” said Dr. Rainer Lichtenberger, COO and CFO of CEVEC. “Next to cytomegalovirus, influenza and others, this is another striking example that CAP cells can efficiently propagate disease relevant human viruses.”

CEVEC contracted Paragon to conduct the evaluation study due to its experience working with cell lines on similar projects. Representatives from both companies said they hope the results not only lead to the development of a commercial RSV vaccine but also prove the CAP technology’s potential as a production system also in the vaccine market. “We were very excited about the results and hopeful that the CEVEC cell line will become a major manufacturing platform—not just RSV but also other viral vectors,” Phillip Wills, vice president of business development at Paragon, tells DDNews.

CEVEC hopes the positive findings from its study will attract support from potential partners interested in developing an RSV vaccine. Although there is an effective treatment for RSV, “We’re a small company, with limited resources, so we are looking for partners who will be willing to work with us on this,” says Boch. “There’s definitely a need for this vaccine.”