Ovarex
OvaRex® MAb for Ovarian Cancer
About Ovarian Cancer
OvaRex® MAb
for Ovarian Cancer
OvaRex® MAb is a murine monoclonal antibody developed by ViRexx that has a high degree of specificity to a tumor associated antigen (CA125) that is over-expressed by the majority of late stage ovarian cancer patients. The Company believes that the product acts as an immunotherapeutic agent by inducing and/or amplifying the human body's immune response against ovarian cancer.
OvaRex® MAb (oregovomab)
• a fully foreign monoclonal antibody
(MAb) that targets CA125 in circulation
• induces broad immune responses against CA125 and patients own ovarian
tumor
• in final stages of clinical development – phase II complete
• benign safety profile and good quality of life during treatment
• administration is a 20 minute IV infusion, low dose (2 mg) , 4 - 5 times/year
The OvaRex® clinical program includes:
• patients in
remission following first-line treatment
of surgery and chemotherapy
• patients whose disease has relapsed (clinically or biochemically)
• patients who are refractory - they no longer respond to chemotherapy
In the United States, Canada and Europe, ovarian cancer causes more deaths than any other cancer of the female reproductive tract. It is estimated that in the United States, approximately 23,000 new cases of ovarian cancer were diagnosed and approximately 14,000 women will die from this disease annually (American Cancer Society, 2000 Cancer Facts & Figures). An almost equal number of new (incidence) and existing (prevalence) cases occur in Europe.
Ovarian cancer
• the most deadly of gynecologic cancers,
affecting 1 in 55 women in the U.S.
• exhibits vague symptoms, therefore called "The Disease That Whispers"
• location of the ovaries makes the disease difficult to detect
• typically not diagnosed until late stages of disease when it has already
spread beyond the ovaries
• first-line treatment is surgery followed by chemotherapy
• average survival 30 months, 5 year survival only about 20% (stage III/IV)
Although detection of ovarian cancer at an early stage is now associated with
an improved chance for curative treatment, survival figures have not changed
significantly over the past 15 years. This is partially due to a lack of
efficient diagnostic methods or markers for routine tests that could increase
the number of patients diagnosed at the early stage of their disease. Consequently,
in approximately three-quarters of diagnosed patients, the tumor has already
progressed to an advanced stage (Stage III or IV), making treatment much
more difficult.
Of these Stage III and IV patients, more than 80% express the tumor associated
antigen CA125. The therapeutic approach prescribed for those patients whose
tumors have progressed to an advanced stage consists of surgery (debulking)
in combination with adjuvant chemotherapy, which improves the patient's prognosis,
particularly if the residual tumor is smaller than two centimeters in diameter.
Despite the high rate of patients whose advanced stage cancer enters into clinical
remission, 90% of them will eventually suffer a recurrence of their disease.
(Hoskins et al., Journal of Clinical Oncology, October 1992). Those patients
who either have residual tumors larger than two centimeters or are left with
progressive disease, or a no change situation after first-line chemotherapy,
have a particularly poor prognosis. These individuals typically require additional
chemotherapy within a period of only a few weeks or months. Second-line chemotherapy,
however, suffers from a lack of suitable therapeutic agents as the tumors can
become chemo-resistant due to their inherent heterogeneity and adaptability
to preceding first-line treatment.
In recent years, new chemotherapeutic agents used either as single treatments
or in combination with other therapeutic agents have demonstrated an increase
in survival time by as much as 50%. However, despite their apparent positive
effect on survival time, these agents are generally associated with significant
toxicity and side effects that reduce the patient's quality of life. Given
the rigors of repeated chemotherapeutic treatments, and taking into account
the low response rates and the modest effects on survival time, patient quality
of life has become a major issue. This is increasingly true as ovarian cancer
affects a large number of older and postmenopausal women.