Oral ZYVOX(r) Shows Cost Savings for Treatment of Skin Infections

Newswise — Oral ZYVOX® (linezolid) was associated with significant savings to the health care system – an average of $4,630 per patient – compared to vancomycin when used in an outpatient setting for people with certain infections, according to data to be presented today at the Infectious Diseases Society of America (IDSA) annual meeting. In the study, patients taking oral ZYVOX had fewer physician office visits, emergency room visits, hospitalizations, lab tests and other health care services, as well as lower total costs, compared to patients taking vancomycin.

The study retrospectively analyzed longitudinal claims data from more than 80 health plans for patients treated with ZYVOX or vancomycin on an outpatient basis for infections of which approximately half (48 percent) were skin infections. The average total cost per patient, including drug acquisition and administration as well as all related medical expenses, was 34 percent less for patients who were treated with oral ZYVOX compared with patients who were treated with vancomycin, which must be taken intravenously. ZYVOX is available in interchangeable IV and oral formulations.

“This new information broadens our understanding of the benefits of oral linezolid,” said Peggy S. McKinnon, PharmD, Clinical Pharmacist, Transplant Infectious Diseases/Clinical Research at the Barnes-Jewish Hospital in St. Louis, Mo. and lead investigator. “Using an oral agent eliminates the risk of IV complications, such as line infections, as well as the cost of IV administration. This study offers further evidence of the cost savings of oral linezolid to the health care system.”

Study Background
McKinnon and other investigators conducted a retrospective study using claims data from more than 80 health care plans to evaluate the impact of outpatient treatment with oral ZYVOX versus IV vancomycin on resource utilization and direct medical costs. The study analyzed 1,048 adult patients treated with ZYVOX and 1,048 adult patients treated with vancomycin, matched by propensity score, between January 2002 and March 2004. Demographic, clinical and resource utilization data were collected for 12 months prior and during the 35 day observation period, including treatment duration. Demographic and clinical characteristics, such as age, gender, plan type, comorbidities, infection-related events, and total health care costs, were comparable between treatment groups for 12 months prior to treatment. Neither efficacy nor safety was evaluated in this study.

Study Results
During the follow-up period, 35 days after treatment, patients who received oral ZYVOX used significantly fewer health care resources in the six areas studied, including physician office visits (4.1 vs. 8.4 visits per patient; p<0.0001), emergency room visits (0.13 vs. 0.17; p=0.003), diagnostic claims (6.3 vs. 10.4; p<0.0001), other outpatient claims (8.9 vs. 18.4; p<0.0001), pharmacy claims (7.3 vs. 13.6; p<0.0001) and hospitalizations (0.19 vs. 0.23; p=0.024). The average total cost of care per patient was $4,630 (34 percent) less for ZYVOX patients compared with vancomycin patients ($8,922 vs. $13,552; p<0.0001).

“In short, patients were able to recover at home with less medical intervention than patients taking vancomycin,” said Yehuda Carmeli, MD, MPH, Beth Israel Deaconess Medical Center, Boston, Mass. and study investigator. “As the medical community strives to provide the best patient care while containing costs, these are important data for physicians to take under consideration.”

About ZYVOX
ZYVOX was initially approved in the United States in April 2000 for the treatment of complicated skin and skin structure infections (cSSSIs) and nosocomial pneumonia, including those caused by methicillin-resistant Staphylococcus aureus (MRSA), a serious bacteria linked to increased morbidity, mortality and costs. ZYVOX is available in interchangeable IV and oral formulations, and is the only oral medicine approved by the U.S. Food and Drug Administration for the treatment of designated infections due to MRSA. In December 2002, ZYVOX was approved for use in pediatric patients and subsequently received approval for diabetic foot infections in July 2003. Since its introduction, ZYVOX has proven to be an important treatment option for designated infections known or suspected to be caused by MRSA. To date, more than one million patients worldwide have been treated with ZYVOX for its approved indications.

ZYVOX is indicated in the treatment of the following infections caused by susceptible strains of the designated microorganisms:

• Complicated skin and skin structure infections, including diabetic foot infections, without concomitant osteomyelitis, caused by Staphylococcus aureus (methicillin-susceptible and -resistant strains), Streptococcus pyogenes, or Streptococcus agalactiae. ZYVOX has not been studied in the treatment of decubitus ulcers. Combination therapy may be clinically indicated if the documented or presumptive pathogens include Gram-negative organisms.Nosocomial pneumonia caused by Staphylococcus aureus (methicillin-susceptible and-resistant strains) or Streptococcus pneumoniae (including multidrug-resistant strains [MDRSP]*). Combination therapy may be clinically indicated if the documented or presumptive pathogens include Gram-negative organisms.

ZYVOX formulations are contraindicated for use in patients who have known hypersensitivity to linezolid or any of the other product components.
Myelosuppression (including anemia, leukopenia, pancytopenia, and thrombocytopenia) has been reported in patients receiving linezolid. In cases where the outcome is known, when linezolid was discontinued, the affected hematologic parameters have risen toward pretreatment levels. Complete blood counts should be monitored weekly in patients who receive linezolid,
particularly in those who receive linezolid for longer than 2 weeks, those with preexisting myelosuppression, those receiving concomitant drugs that produce bone marrow suppression, or those with a chronic infection who have received previous or concomitant antibiotic therapy. Discontinuation of therapy with linezolid should be considered in patients who develop or have worsening myelosuppression.

Lactic acidosis has been reported with the use of ZYVOX. In reported cases, patients experienced repeated episodes of nausea and vomiting. Patients who develop recurrent nausea or vomiting, unexplained acidosis, or a low bicarbonate level while receiving ZYVOX should receive immediate medical evaluation.

Spontaneous reports of serotonin syndrome associated with co-administration of ZYVOX and serotonergic agents, including antidepressants such as selective serotonin reuptake inhibitors (SSRIs), have been reported. Patients who are treated with ZYVOX and concomitant serotonergic agents should be closely observed for signs and symptoms of serotonin syndrome (e.g., cognitive dysfunction, hyperpyrexia, hyperreflexia, incoordination). If any signs or symptoms occur physicians should consider discontinuation of either one or both agents (ZYVOX or concomitant serotonergic agents).

Peripheral and optic neuropathy have been reported in patients treated with ZYVOX, primarily those patients treated for longer than the maximum recommended duration of 28 days. In cases of optic neuropathy that progressed to loss of vision, patients were treated for extended periods beyond the maximum recommended duration. Visual blurring has been reported in some patients treated with ZYVOX for less than 28 days.

If patients experience symptoms of visual impairment, such as changes in visual acuity, changes in color vision, blurred vision, or visual field defect, prompt ophthalmic evaluation is recommended. Visual function should be monitored in all patients taking ZYVOX for extended periods (≥3 months) and in all patients reporting new visual symptoms regardless of length of therapy with ZYVOX. If peripheral or optic neuropathy occurs, the continued use of ZYVOX in these patients should be weighed against the potential risks.

The most commonly reported adverse events in adults across clinical trials were nausea, headache, and diarrhea.

To reduce the development of drug-resistant bacteria and maintain the effectiveness of ZYVOX and other antibacterial drugs, ZYVOX should be used only to treat or prevent infections that are proven or strongly suspected to be caused by susceptible bacteria. When culture and susceptibility information are available, they should be considered in selecting or modifying antibacterial therapy. In the absence of such data, local epidemiology and susceptibility patterns may contribute to the empiric selection of therapy.

As with nearly all antibacterial agents, pseudomembranous colitis has been reported with ZYVOX. Therefore, it is important to consider this diagnosis in patients who present with diarrhea subsequent to the administration of ZYVOX.

*MDRSP refers to isolates resistant to 2 or more of the following antibiotics: penicillin, second-generation cephalosporins, macrolides, tetracycline, and trimethoprim/sulfamethoxazole.

Full prescribing information is available upon request or please visit http://www.pfizer.com or http://www.zyvox.com.