SAN FRANCISCO — Patients with sickle cell disease who receive prescription-grade oral L-glutamine experienced fewer painful sickle cell crises and hospitalizations than patients who received placebo, according to phase 3 study results presented at the ASH Annual Meeting and Exposition.
Pharmaceutical grade oral L-glutamine (PGLG) also was associated with a reduced incidence of acute chest syndrome, a delay in time to first sickle cell crisis and a shorter hospital length of stay, results showed.
“We are pleased to present at the ASH meeting the positive safety and efficacy results of our phase 3 trial of PGLG in treating sickle cell patients,” Yutaka Niihara, MD, CEO of Emmaus Life Sciences, told HemOnc Today. “We believe the results demonstrate a well-tolerated safety profile that has the potential to help adult and pediatric patients who are in need of new therapies to treat this disease.”
Niihara and colleagues evaluated data from 230 patients with sickle cell anemia or beta-zero thalassemia who had at least two episodes of sickle cell crises. Patients were aged 5 to 58 years; 53.9% were female.
Researchers assigned patients 2:1 to 0.6 g/kg daily PGLG (Emmaus Life Sciences; n=152) or placebo (n=78). After 48 weeks of treatment, the dosage was tapered to 0 g/kg for 3 weeks.
Significantly fewer median episodes of sickle cell crises occurred among patients who received PGLG compared with those who received placebo (3 vs. 4; P=.008). The median time to first sickle cell crisis was 54 days in the placebo arm, whereas patients who receive PGLG experienced a delay in time to first crisis of 87 days (P=.01).
Patients who received the study treatment were hospitalized a median of two times, whereas patients in the placebo arm were hospitalized a median of three times (P=.005). Use of PGLG was associated with a 41% reduction in hospital length of stay (6.5 days vs. 11 days; P=.022).
Acute chest syndrome occurred significantly more frequently in the placebo arm than in the PGLG arm (26.9% vs. 11.9%; P=.006).
Researchers noted the improvements associated with PGLG persisted after researchers stratified data for hydroxyurea use, age and gender.
Adverse events were similar in both arms.
“L-glutamine seemed to reduce the incidence of painful crises, but if patient did have a crisis, the chance of a patient being hospitalized was less,” Niihara said during a press briefing. “If they had to be hospitalized, they seemed to stay in the hospital for a shorter duration, and they had a smaller chance of going to the ICU for acute chest syndrome. So overall, we felt that L-glutamine not only reduced the frequency of painful crises, but [also] perhaps the severity of the crisis itself was reduced.”
Researchers are planning future studies on the use of PGLG in infants, pregnant women and in combination with hydroxyurea, Niihara said.
For more information:
Niihara Y. Abstract #86. Presented at: ASH Annual Meeting and Exposition; Dec. 6-9, 2014; San Francisco.
Disclosure: Niihara reports employment with and equity ownership in Emmaus Life Sciences. Other researchers report employment with and equity ownership in Emmaus Medical Inc. One researcher reports a consultant role with Pfizer.