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Because most HCT recipients are expected to face a natural viral challengeas pre-existing CMV infection reactivates under immunosuppression, the primaryefficacy endpoint in the double-blind, placebo-controlled Phase 2 trial is theoccurrence rate of clinically significant CMV levels in HCT patients receivingvaccine compared with patients receiving placebo. Other important endpointsinclude immune responses against the specific CMV features targeted by thevaccine. The trial also is comparing safety of the vaccine against placebo inup to 80 matched, related HCT donors and recipients, and up to 80 additionalHCT recipients. The DSMB evaluated safety data only in the interim analysis.
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About CMV
CMV is a herpes virus that infects more than half of all adults in theUnited States by age 40, and is even more widespread in developing countries.While a healthy immune system typically protects an infected person againstCMV disease, it rarely succeeds in completely eliminating the infection, andthose whose immune systems are not fully functional are at high risk of CMVproliferation, potentially leading to severe illness or death. These includetransplant patients who take immunosuppressive drugs, and fetuses and newbornsof mothers who first become infected during pregnancy.
CMV infection affects 30 to 60 percent of the patients undergoing varioustransplant procedures, causing transplant rejection, serious illness and evendeath if untreated. Expensive antiviral drug therapy is used to control thedisease, but does not eliminate the infection. Congenital CMV infectionaffects one out of every hundred infants, and causes severe consequences inabout 3,600 infants and death in about 400 each year in the United States.
There is no approved vaccine against CMV. Vaccine approaches that resultin predominantly antibody responses to CMV have not proven highly effective intransplant patients. Vaccine approaches using live, attenuated viruses caninduce both antibody and cellular immune responses, but pose a potentialsafety concern, particularly for immunocompromised patients, of causing thedisease they are intended to prevent. Vical's novel DNA vaccine approach isdesigned to induce both antibody and cellular immune responses againstspecific features of the CMV virus without the risk of causing CMV disease.Vical's vaccine has received orphan drug designation for hematopoietic stemcell transplant and solid organ transplant patients.
About Vical
Vical researches and develops biopharmaceutical products based on itspatented DNA delivery technologies for the prevention and treatment of seriousor life-threatening diseases. Potential applications of the company's DNAdelivery technology include DNA vaccines for infectious diseases or cancer, inwhich the expressed protein is an immunogen; cancer immunotherapeutics, inwhich the expressed protein is an immune system stimulant; and cardiovasculartherapies, in which the expressed protein is an angiogenic growth factor. Thecompany is developing certain infectious disease vaccines and cancertherapeutics internally. In addition, the company collaborates with majorpharmaceutical companies and biotechnology companies that give it access tocomplementary technologies or greater resources. These strategic partnershipsprovide the company with mutually beneficial opportunities to expand itsproduct pipeline and address significant unmet medical needs. Additionalinformation on Vical is ava
