STUDIES ON PNEUMONIA IN CHILDREN: I. Mortality, Blood Cultures, and Humoral Antibodies in Pneumococcus Pneumonia

CERTAIN ASPECTS OF MOUSE PROTECTION TESTS FOR ANTIBODY IN PNEUMOCOCCUS PNEUMONIA

1. Though in general in pneumococcus pneumonia the appearance of protective substance coincides rather sharply with the fall in the temperature, antibody may appear spontaneously in the blood serum as early as the 3rd or 4th day and crisis and recovery may be delayed until the 6th to the 10th day. 2. Recovery at times occurs without demonstrable protective substance in the blood in patients who later develop protection. 3. The amount of antibody developed in the course of pneumococcus pneumonia is small and in the majority of cases tested was insufficient to protect against more than 100 lethal doses of homologous pneurnococci and never against more than 10,000 lethal doses. 4. Treatment with Felton's antibody late in the course of the disease materially increases the amount of protective substances in the blood. A high degree of protection may be established by treatment in fatal cases. After the 3rd day doses of more than 200,000 Felton units are usually necessary to produce a greater degree of protection than might otherwise be expected. 5. The formation of protective substances by the patient himself is not an assurance against progress of the infection to a fatal termination. 6. Protective substance in the blood and pneumococcic septicemia may occur simultaneously.

Effects of prior effective therapy on the efficacy of daptomycin and ceftriaxone for the treatment of community-acquired pneumonia

OBJECTIVE

We sought to compare daptomycin with ceftriaxone for the treatment of patients with community-acquired pneumonia (CAP).

METHODS

Two phase-3 randomized, double-blind trials that enrolled adult patients hospitalized with CAP were conducted. Patients received intravenous daptomycin (4 mg/kg) or ceftriaxone (2 g) once daily for 5-14 days. Aztreonam could be added for patients with gram-negative infections. Clinical responses at the test-of-cure visit among patients in the intent-to-treat and clinically evaluable populations were the primary efficacy end points.

RESULTS

After combining data from the trials, the intent-to-treat population included 413 daptomycin-treated patients and 421 ceftriaxone-treated patients, and the clinically evaluable population included 369 daptomycin-treated patients and 371 ceftriaxone-treated patients. In the intent-to-treat population, the clinical cure rate among daptomycin-treated patients with CAP was 70.9%, compared with 77.4% among ceftriaxone-treated patients (95% confidence interval for the difference between cure rates, -12.4% to -0.6%). In the clinically evaluable population, the clinical cure rate was lower among daptomycin-treated patients (79.4%) than among ceftriaxone-treated patients (87.9%; 95% confidence interval for the difference between cure rates, -13.8% to -3.2%). A posthoc analysis revealed that, among those who had received up to 24 h of prior effective therapy, cure rates were similar among daptomycin-treated (90.7%) and ceftriaxone-treated patients (88.0%; 95% confidence interval for the difference between cure rates, -6.1% to 11.5%).

CONCLUSIONS

Daptomycin is not effective for the treatment of CAP, including infections caused by Streptococcus pneumoniae and Staphylococcus aureus. The observation that as little as 24 h of prior effective therapy may impact clinical outcome suggests that trials to evaluate CAP treatment may need to exclude patients who have received any potentially effective therapy before enrollment.