First-in-human Phase I study of EZN-4176, a locked nucleic acid antisense oligonucleotide to exon 4 of the androgen receptor mRNA in patients with castration-resistant prostate cancer

BACKGROUND

Prostate cancer remains dependent of androgen receptor (AR) signalling, even after emergence of castration resistance. EZN-4176 is a third-generation antisense oligonucleotide that binds to the hinge region (exon 4) of AR mRNA resulting in full-length AR mRNA degradation and decreased AR protein expression. This Phase I study aimed to evaluate EZN-4176 in men with castration-resistant prostate cancer (CRPC).

METHODS

Patients with progressing CRPC were eligible; prior abiraterone and enzalutamide treatment were allowed. EZN-4176 was administered as a weekly (QW) 1-h intravenous infusion. The starting dose was 0.5 mg kg(-1) with a 4-week dose-limiting toxicity (DLT) period and a 3+3 modified Fibonacci dose escalation design. After determination of the DLT for weekly administration, an every 2 weeks schedule was initiated.

RESULTS

A total of 22 patients were treated with EZN-4176. At 10 mg kg(-1) QW, two DLTs were observed due to grade 3-4 ALT or AST elevation. No confirmed biochemical or soft tissue responses were observed. Of eight patients with <5 circulating tumour cells at baseline, a conversion to <5 was observed in three (38%) patients. The most common EZN-4176-related toxicities (all grades) were fatigue (59%), reversible abnormalities in liver function tests ALT (41%) and AST (41%) and infusion-related reactions including chills (36%) and pyrexia (14%).

CONCLUSION

Activity of EZN-4176 at the doses and schedules explored was minimal. The highest dose of 10 mg kg(-1) QW was associated with significant but reversible transaminase elevation.

Epidemiology and outcomes of deep surgical site infections following lung transplantation

We conducted a retrospective study of deep surgical site infections (SSIs) among consecutive patients who underwent lung transplantation (LTx) at a single center from 2006 through 2010. Thirty-one patients (5%) developed SSIs at median 25 days after LTx. Empyema was most common (42%), followed by surgical wound infections (29%), mediastinitis (16%), sternal osteomyelitis (6%), and pericarditis (6%). Pathogens included Gram-positive bacteria (41%), Gram-negative bacteria (41%), fungi (10%) and Mycobacterium abscessus, Mycoplasma hominis and Lactobacillus sp. (one each). Twenty-three percent of SSIs were due to pathogens colonizing recipients' native lungs at time of LTx, suggesting surgical seeding as a source. Patient-related independent risk factors for SSIs were diabetes and prior cardiothoracic surgery; procedure-related independent risk factors were LTx from a female donor, prolonged ischemic time and number of perioperative red blood cell transfusions. Mediastinitis and sternal infections were not observed among patients undergoing minimally invasive LTx. SSIs were associated with 35% mortality at 1 year post-LTx. Lengths of stay and mortality in-hospital and at 6 months and 1 year were significantly greater for patients with SSIs other than empyema. In conclusion, deep SSIs were uncommon, but important complications in LTx recipients because of their diverse microbiology and association with increased mortality.

Lung transplantation in patients with prior cardiothoracic surgical procedures

The full spectrum of prior cardiothoracic procedures in lung transplant candidates and the impact of prior procedures on outcomes after lung transplantation (LTx) remain unknown, though the impact is considered to be large. Patients transplanted at our institution from 2004 to 2009 were identified (n = 554) and divided into two groups: patients who had undergone cardiothoracic surgical (CTS) procedures prior to LTx (n = 238) and patients who had not (non-CTS: n = 316). Our primary endpoint was survival. Secondary endpoints included allograft function and the incidence of major complications including reexploration due to bleeding, prolonged ventilation, renal insufficiency and primary graft dysfunction. Long-term survival was not significantly different between the groups whereas postoperative bleeding, nerve injury, respiratory and renal complications were higher in the CTS group. Posttransplant peak FEV1 was lower in the CTS group (73.4% vs. 86.9%, p < 0.05). In multivariate analysis, performance of a chemical pleurodesis procedure and prolonged cardiopulmonary bypass were significantly associated with mortality (OR, 1.7; CI, 1.5-2.0; p < 0.005). Our results suggest that patients with LTx and prior CTS remain technically challenging and experience worse outcomes than patients without prior CTS. A surgical strategy to minimize cardiopulmonary bypass time is critical for these challenging LTx patients.

Hyperkalemic distal renal tubular acidosis caused by immunosuppressant treatment with tacrolimus in a liver transplant patient: case report

Nephrotoxicity is one of the most common side effects of long-term immunosuppressive therapy with calcineurin inhibitors. We describe a case of distal renal tubular acidosis secondary to tacrolimus administration. A 43-year-old man with end-stage liver disease due to hepatitis C and B virus infections and alcoholic cirrhosis received a liver transplantation under immunosuppressive treatment with tacrolimus and mycophenolate mofetil. In the postoperative period, the patient developed hyperkalemic hyperchloremic metabolic acidosis, with a normal serum anion gap and a positive urinary anion gap, suggesting distal renal tubular acidosis. We excluded other causes of hyperkalemia. Administration of intravenous bicarbonate, loop diuretics, and oral resin exchanger corrected the acidosis and potassium levels. Distal renal tubular acidosis is one of several types of nephrotoxicity induced by tacrolimus treatment, resulting from inhibition of potassium secretion in the collecting duct. Treatment to correct the acidosis and hyperkalemia should be promptly initiated, and the tacrolimus dose adjusted when possible.

First Report of Mango Malformation Disease Caused by Fusarium mangiferae in Spain

Mango (Mangifera indica L.) malformation disease (MMD) is one of the most important diseases affecting this crop worldwide, which causes severe economic losses because of the reduction of productivity. Symptoms of MMD in Spain were observed for the first time in April of 2006 in three mango orchards in the Axarquia Region (southern Spain). Symptoms included an abnormal development of vegetative shoots with shortened internodes and dwarfed leaves and hypertrophied short and thickened panicles. In the years of 2006, 2009, and 2010, isolates of Fusarium were obtained from vegetative shoots and floral tissue of symptomatic mango trees from 21 different orchards of cvs. Keitt, Kent, Osteen, Tommy Atkins, and a variety of minor commercial cultivars, all showing typical symptoms of MMD. Different Fusarium-like strains were isolated from infected tissues. Colonies from single-spored isolates possessed dark purple-to-salmon-colored mycelium when grown on potato dextrose agar medium. On fresh carnation leaf agar medium, mycelium contained aerial conidiophores possessing three- to five-celled macroconidia and abundant microconidia in false heads from mono- and polyphialides; while cream-orange-colored sporodochia were produced on the surface of the medium, typical for Fusarium mangiferae. The identification of 37 isolates was confirmed as F. mangiferae by species-specific PCR analysis with the primer pair 1-3 F/R that amplified a 608-bp DNA fragment from all Spanish isolates as well as a representative Israeli control strain, Fus 34, also designated as MRC7560 (2). Pathogenicity using four representative isolates, UMAF F02, UMAF F10, UMAF F17, and UMAF F38 of F. mangiferae from Spain as well as isolate MRC7560, was tested on 2-year-old healthy mango seedlings cv. Keitt by inoculating 15 buds from three different trees with a 20-μl conidial suspension (5 × 10⁷ conidia per ml) per isolate (1). This experiment was conducted twice with two independent sets of plants and at different times (March and November 2010). Typical mango malformation symptoms were detected after bud break in March 2011, 5 and 12 months after inoculation. Symptoms were observed for 60% of the inoculated buds with the four F. mangiferae Spanish isolates and 75% with the MRC7560 control strain, but not with water-inoculated control plants. Recovered isolates from the infected floral and vegetative malformed buds were identical morphologically to those inoculated, and the specific 608-bp fragment described for F. mangiferae was amplified with specific-PCR, thus fulfilling Koch's postulates. To our knowledge, this is the first report of mango malformation disease caused by F. mangiferae in Spain and Europe. References: (1) S. Freeman et al. Phytopathology 89:456, 1999. (2) Q. I. Zheng and R. C. Ploetz. Plant Pathol. 51:208, 2002.

HIV, HEV and cirrhosis: evidence of a possible link from eastern Spain

OBJECTIVES

The aim of the study was to assess the seroprevalence of hepatitis E virus (HEV) infection in an HIV-infected population, as determined by HEV immunoglobulin G (IgG) antibodies (anti-HEV).

METHODS

The design of the study was cross-sectional. Serum anti-HEV IgG was determined by enzyme immunoassay in 238 HIV-infected patients consecutively attending our out-patient clinic between April and May 2011. In HEV-seropositive patients, HEV RNA was analysed by nested reverse transcriptase-polymerase chain reaction (RT-PCR). Associations between anti-HEV and liver cirrhosis, route of HIV infection, hepatitis B virus (HBV) and hepatitis C virus (HCV) serological markers, age, sex and alanine aminotransferase (ALT) levels were examined by univariate and multivariate analysis.

RESULTS

One hundred and forty patients (59%) had chronic liver disease (99% were HBV- and/or HCV-coinfected). Liver cirrhosis was detected in 44 individuals (19%). Two hundred and twelve patients (89%) were on antiretroviral treatment; the median CD4 T-cell count was 483 cells/μL [interquartile range (IQR) 313-662 cells/μL] and the HIV viral load was <25 HIV-1 RNA copies/mL. Overall, 22 patients (9%) were anti-HEV positive. Liver cirrhosis was the only factor independently associated with the presence of anti-HEV, which was documented in 23% of patients with cirrhosis and 6% of patients without cirrhosis (P=0.002; odds ratio 5.77). HEV RNA was detected in three seropositive patients (14%), two of whom had liver cirrhosis.

CONCLUSIONS

Our findings show a high prevalence of anti-HEV in HIV-infected patients, strongly associated with liver cirrhosis. Chronic HEV infection was detected in a significant number of HEV-seropositive patients. Further research is needed to ascertain whether cirrhosis is a predisposing factor for HEV infection and to assess the role of chronic HEV infection in the pathogeneses of cirrhosis in this population.