Updated from 2:25 p.m. EDT

Ortho Biotech Products and

Amgen

(AMGN) - Get Report

offered dueling results of their products for fighting chemotherapy-induced anemia, with both presenting statistics that show their treatments appear to be plenty effective.

In a press release, Ortho Biotech says a study demonstrated that its Procrit increased hemoglobin levels more than Amgen's Aranesp in patients with cancer and anemia caused by chemotherapy.

The company says the results show that 47% of patients treated with Procrit achieved the primary endpoint of the study, an increase in hemoglobin of one gram or more per deciliter of blood within the first four weeks, compared with 33% of patients who were treated with Aranesp. The difference is statistically significant, Ortho says.

The results were presented at the annual meeting of the American Society of Clinical Oncology. Ortho Biotech is part of

Johnson & Johnson

(JNJ) - Get Report

.

Patients treated with Procrit were transfused with fewer units of red blood cells during the study. Transfused patients treated with Procrit received a mean of 2.5 units of red blood cells per patient, while transfused patients treated with Aranesp received a mean of 3.9 units of red blood cells per patient, a statistically significant difference, Ortho Biotech reported.

Meanwhile, Amgen countered with data saying the final results of a study found that Aranesp administered every two weeks is as effective as epoetin alfa -- marketed by Ortho as Procrit and by Amgen under the name Epogen -- dosed once a week in boosting hemoglobin levels and reducing the need for red blood cell transfusions to treat anemia caused by chemotherapy.

Amgen says 1,220 patients with anemia were randomized to receive either Aranesp 200 mcg every two weeks or epoetin alfa 40,000 U once a week. The majority of patients in both groups achieved the target hemoglobin of greater than or equal to 11 g/dL.

In this study, at least 90% of patients in both arms of the study achieved target hemoglobin of greater than or equal to 11 g/dL. The study's primary endpoint was designed to evaluate non-inferiority with respect to transfusion rates. Both companies agreed that their separate studies found similar blood transfusion rates and safety profiles.