Genitope next year will likely submit its new personalized immunotherapy for follicular non-Hodgkin’s lymphoma for US Food and Drug Administration approval, Pharmacogenomics Reporter has learned.
A spokesperson representing Genitope told Pharmacogenomics Reporter last week that the company is “working closely with the FDA to prepare for a potential BLA filing in 2008” if clinical trials “are successful.”
In a release last week, the Redwood City, Calif.-based company announced it had begun a Phase II clinical trial evaluating patients’ response to the drug, called MyVax, following treatment with Rituxan and chemotherapy.
Additionally, Genitope is studying the safety and efficacy of MyVax in a pivotal Phase III trial in previously untreated fNHL patients, which comprise around one-third of all NHL cases in the US.
The company is touting the product as “personalized medicine.” According to Genitope, the drug differs from others currently available because it targets the idiotrope proteins found on the surface of a patient’s tumor cells.
Genitope’s spokesperson would not estimate a potential timeframe to launch the drug.
MyVax “is based on the unique genetic makeup of a patient's own tumor and is designed to activate the patient's immune system to fight cancer,” the company said in a statement.
The drug works by targeting a unique idiotype protein found on the surface of a patient’s tumor cells. The idiotype protein provides a unique “fingerprint” of that tumor, “making it an ideal target for personalized immunotherapy,” the company said. “The treatment is tumor-specific so a patient’s immune system should target only the cancer cells for destruction while leaving normal cells unharmed.”
The single-arm, multi-center Phase II study evaluating the efficacy of MyVax following treatment with Rituxan and chemotherapy will involve enrolling 100 patients from eight leading cancer centers across the US, Genitrope said.
The eligibility criteria for enrollment in the trial will include men and women over age 18 who have treatment-naïve Stage II or IV fNHL, who require and are able to receive Rituxan or chemotherapy.
Patients enrolled in the study will receive between six to eight cycles of R-Chemo, and following a six-month rest period will receive a series of 24 immunizations with MyVax over a 92-week period.
According to Julie Vose, professor of medicine and chief of the Oncology/Hematology section at University of Nebraska Medical Center, one of the centers participating in the study, the trial is important since it may provide additional data on the optimal timing for MyVax therapy following standardized treatment.
"Initial data have suggested that adding MyVax … to the current treatment protocol may extend duration of remission while maintaining a well-tolerated safety profile,” Vose said in a statement.
MyVax is also currently being studied in a pivotal Phase III efficacy and safety trial of 287 previously untreated fNHL patients. In the trial, patients first receive chemotherapy and then enter into a 6-month rest period. Those patients who maintain a partial response for that period are randomized to receive either MyVax or a non-specific immunotherapy.
According to Genitope, the treatment phase of this trial is complete and the follow-up period is slated to close at the end of this year.
Genitope’s confidence in MyVax’s performance in the Phase III trial is perhaps bolstered by long-term follow-up results from an earlier Phase II trial, which showed a significant increase in time-to-progression in patients taking MyVax following chemo compared to chemo alone.
"Initial data have suggested that adding MyVax personalized immunotherapy to the current treatment protocol may extend duration of remission while maintaining a well-tolerated safety profile.”
In that Phase II trial, which followed 21 patients, median time-to-disease-progression was 37.7 months after ending chemotherapy. Nine of the 21 patients remained progression-free up to their last clinical follow-up at 56 to 78 months following the end of chemotherapy.
According to Genitope, “published studies in similar follicular B-cell NHL patients treated with chemotherapy alone have shown a median time-to-disease- progression of 15 months.”
In addition to clinical trials in fNHL, Genitope said it is exploring MyVax to treat other types of B-cell cancers, including previously untreated chronic lymphocytic leukemia.
At this early stage in clinical development, however, the company is mainly highlighting the fact that MyVax, unlike other drugs on the market, is a “customized” patient- and tumor-specific treatment.
NHL patients have few options available to them. Treatment depends on when the cancer is diagnosed and how rapidly the disease is spreading. The cancer is commonly treated with chemotherapy, with Rituxan currently being the standard of care. Other chemotherapeutic regimens include cyclophosphamide, hydroxydaunorubicin, oncovin, and prednisolone; and cyclophosphamide, vincristine, and prednisolone.
According to a spokesperson for Genitope, there are currently no plans to develop a diagnostic for the drug since the mechanism of the drug itself is patient- and tumor-specific.
In fact, the spokesperson said MyVax’s mechanism of action may actually contribute to a better safety profile.
For instance, when chemotherapy depletes too many normal cells, patients accumulate uric acid, which could eventually lead to kidney failure. However, since MyVax specifically targets tumor cells without harming normal cells, patients might experience fewer toxicities such as kidney failure. Due to the lack of available therapies on the market, this improved safety profile may embolden oncologists to start using the drug if it’s approved.
There are currently more than 300,000 people in the US living with NHL. Approximately 55,000 new cases of the disease are diagnosed each year and approximately 32 percent of those people have fNHL.