Efficacy and safety of inhaled recombinant interleukin-2 in high-risk renal cell cancer patients compared with systemic interleukin-2: an outcome study

Systemic IL-2 is an effective treatment for low to intermediate risk mRCC patients, its efficacy is marginal in high-risk cases. Therefore, other treatment approaches are required for this population. Ninety-four high-risk patients with RCC and pulmonary metastases were treated with inhaled plus concomitant low-dose subcutaneous rhIL-2. Clinical response, survival and safety were compared with those from IL-2 given systemically at the registered dose and schedule in 103 comparable historical controls. In the rhIL-2 INH group, treatment consisted of 6.5 MIU rhIL-2 nebulized 5x/day and 3.3 MIU rhIL-2 SC once daily. The rhIL-2 SYS group received treatment which consisted of intravenous infusion of 18.0 MIU/m2/day rhIL-2 or SC injection of 3.6-18.0 MIU rhIL-2. Some patients in both groups also received IFNalpha. Mean treatment durations were 43 weeks rhIL-2 INH and 15 weeks rhIL-2 SYS. Significantly longer overall survival and progression-free survival durations were observed in the rhIL-2 INH group. The probability of survival at 5 years was 21% for the rhIL-2 INH group. No patients survived 5 years in the rhIL-2 SYS group. A multivariate analysis of overall survival adjusting for differences in baseline characteristics between the two treatment groups resulted in a risk ratio of 0.43 (95% CI 0.30-0.63; P < 0.0001). The data suggested an association between the response (SD or better) and survival, especially in the rhIL-2 INH group. The inhalation regimen was well tolerated. This outcome study suggests that administration of rhIL-2 by inhalation is efficacious and safe in high-risk mRCC patients with pulmonary metastases, who have no other treatment option available.

Stable and long-lasting immune response in horses after DNA vaccination against equine arteritis virus

Equine arteritis virus (EAV) is the causative agent of the equine viral arteritis. It is a small RNA virus with a linear, non-segmented plus RNA genome. EAV is a member of the Arteriviridae family that includes porcine reproductive and respiratory syndrome virus (PRSSV), simian haemorrhagic fever virus (SHFV) and lactate dehydrogenase virus (LDV). The viral transmission is via respiratory and reproductive routes. Clinical signs in horses vary, and severe infection can lead to abortions in pregnant mares or neonatal foal death. The aim of this study was to investigate the development of the immune response in horses after immunization with a DNA vaccine harbouring and expressing EAV Open Reading Frames (ORF) 2, 5, and 7, in combination with equine interleukin 2 (eqIL2). Three boosters followed the basic immunization in two-week intervals. Each immunization was a combination of gene gun and intramuscular injection. All horses developed a high titer of neutralizing antibodies after basic immunization within 2 weeks. Remarkably, this immune response was found to be independent of the age of animals. The youngest horse was six-years old, and the oldest twenty-two years old. A remarkable difference in the immune response between the young and old were not observed. The duration of immunity was investigated during a period of one year. After 12 months, neutralizing antibodies were still detectable in all the vaccinated horses.

Esophageal achalasia: intrasphincteric injection of botulinum toxin A versus balloon dilation

BACKGROUND AND STUDY AIMS

In patients with esophageal achalasia, pneumatic dilation is the treatment of choice, but it bears the risk of perforation in about 4% of cases. A new nonsurgical method, intrasphincteric injection of botulinum toxin A, has shown promising initial results, and we thus undertook this study to compare the long-term outcome of these two methods.

PATIENTS AND METHODS

In a prospective randomized study, 24 patients with definitive esophageal achalasia were divided into two equal groups and underwent either balloon dilation or injection of botulinum toxin (20 U injected into each of the four quadrants in the lower esophageal sphincter). The outcome was assessed on the basis of a symptom score documented before treatment and at regular intervals for two and a half years thereafter. Complications associated with the two techniques were also documented.

RESULTS

No relevant complication occurred in either of the treatment groups. Initially, dilation was successful in 10 of 12 patients (83%), and botulinum toxin injection in 9 of 12 patients (75%). The symptom scores showed no significant differences between the two groups before and one month after treatment. Over the two and a half year follow-up, however, all nine successfully treated patients in the botulinum toxin group experienced recurrence of symptoms, but only four of the ten patients (40%) in the dilation group.

CONCLUSIONS

The two treatment methods initially had equal success rates, but in the long term the effect of the botulinum toxin injection was statistically significantly shorter than that of balloon dilation. As fewer risks are associated with the injection treatment, studies should be undertaken either to identify patient subgroups in whom botulinum toxin can be effective long-term or to test substances with longer-lasting effects.