Therapeutic
Considerations
Patient Populations
Optimal use of this antibody is in a setting where short-term protection can
be offered to an at risk population. The company also believes that the antibody
will have efficacy in the treatment of established infections. However, an initial
development pathway which seeks to avoid the difficulties associated with combining the antibody with an antibiotic would
provide an efficacy signal in the most efficient and least ambiguous fashion. A positive efficacy signal would permit subsequent
development in prophylactic, adjuvant and established infection settings. In
terms of use of the antibody as a single agent, two settings present themselves – prior to exposure (prophylactic therapy)
or following colonization or treatment of an infection (adjuvant therapy).
Prophylactic Therapy
The first setting, prophylaxis, would involve patients entering the hospital
for procedures where there is a well defined risk of a subsequent infection. A target population would include, but not be
limited to, patients undergoing coronary artery bypass grafts, hemodialysis, bone fractures, hip and knee replacements and
wound debridement. Approximately 2.4 million patients are admitted to private
US hospitals each year for those procedures. Within this group patients whose other
risk factors place them at increased risk would be selected for treatment. This
subset itself represents a major market opportunity and unmet medical need.
Adjuvant Therapy
The second setting, adjuvant therapy, would be in patients noted to have MRSA
colonization or following treatment for an MRSA infection after discharge from the hospital or intensive care unit (ICU). One-third of these patients developed a subsequent infection, regardless of whether
the initial MRSA exposure was colonization or infection. MRSA colonization is not an uncommon problem. Studies of patients admitted to ICUs, the location where surveillance cultures are commonly performed,
have noted that that 20% of patients are or become colonized with MRSA. With
annual intensive care unit admissions in the United States
estimated to be 4.4 million patients approximately 880,000 patients are at risk. This
again represents a major market opportunity and unmet medical need.
Multiple Potential Indications
Given the broad potential utility of this antibody there are multiple indications that
could be pursued. Those include but are not limited to:
-
Prevention of S. Aureus infections in highly susceptable populatins:
-
Orthopedic patients
-
Cardiac by-pass patients
-
Renal dialysis patients
-
Adjuvant therapy for recently discharged ICU patients who have been
-
Established infectins in combination with antibiotics
As PNAG is also present on other bacteria the utility of the antibody can also extend
to other infections two of which are listed below.
- Prevention of E. Coli infections
- Prevention
of S. epidermidis prosthesis infections or bacteremia emanating from a contaminated/infected catheter.
Other uses for mAb F598 are envisioned as well and may include:
use as a component of a diagnostic kit for staph infections; as prophylaxis, treatment or therapy for organisms expressing
the PNAG target antigen in selected patient populations e.g. cystic fibrosis patients; use in animals, where chronic or repeated
Staph infections are encountered.
