Current Clinical Pharmacology - Volume 13, Issue 3, 2018

Background: The molecular mechanism of silencing genes using small interference RNA is as particular and innovative phenomenon as the proposed delivery systems to release them. Recent advances in RNAi have resulted in the development of multiple siRNA candidates that are currently being evaluated in preclinical / clinical instances. SNALP®, Atuplex® and Rondel® technologies stand out; they are mainly based on polymers, cyclodextrins or lipids. Method: The objective of this work is to review the main features that Gene Therapy Medicinal Product under current clinical evaluation present from a pharmaceutical technology point of view; it tries to bring up theoretical concepts that give scientific support to the interpretation of data obtained during pharmaceutical development process. It is basically focused on improving the translation from bench/theoretical concepts to bedside of non viral vectors carrying siRNA. Results: The extensive presence of lipid-based nanoparticle non-viral systems in clinical stages is due to the advantages of their formulations. These include: safety, low immunogenicity, high degree of material properties control, function tuning and ability to impact pharmacokinetics and in vivo biodistribution. This work presents a pharmaceutical approach so as to improve the potential of success in siRNA delivery using liposomal systems. Conclusion: Formulation design should be increasingly addressed with industrial criteria; it should be based on quality by design and on the estimation of critical attributes that affect product performance, and supported by a range of characterization techniques and appropriate analytical methods.

Background: Irritable bowel syndrome (IBS) is the most frequently diagnosed functional gastrointestinal disorder. It is characterised by abdominal pain, bloating and changes in bowel habits that can have a serious impact on the patient's quality of life. Treatment strategies are based on the nature and severity of the symptoms, the degree of functional impairment of the bowel habits, and the presence of psychosocial disorders. The purpose of this review is to update our current knowledge of therapeutic approach of this disorder. Method: A literature search for IBS therapy was carried out using the online databases of Pubmed, Medline and Cochrane. Results: An ideal treatment begins by explaining this condition and providing reassurance to the patients. There is limited evidence for the efficacy, and tolerability of the therapies currently available for the treatment of IBS. There is also a limited availability of pharmacological agents licensed specifically for the treatment of IBS subtypes, although new agents have been recently proposed to this goal. Furthermore, patients often associate their complaints with the ingestion of foods containing FODMAPs (fermentable oligo-di-monosaccharides, and polyols) and gluten derivates and a personalized diet can be proposed. However, more severe symptoms can be associated with greater levels of psychosocial problems and a psychological approach and antidepressant drugs can be needed. Conclusion: The treatment of IBS remains focused on treating the patient's predominant, or most troublesome, symptoms. New promising treatments have recently become available for the treatment of IBS but long term studies are still needed.

Background: RNA interference (RNAi) is a process for regulating the gene expression in which small interfering RNAs (siRNAs) silence target genes. siRNA-based therapy as a new molecular treatment approach, offers therapeutic prospects for many common diseases such as cancer and cardiovascular disorders. Nevertheless, the efficacy of siRNA delivery has, so far, remained a challenging issue. This is due to their easy degradation through the circulation system and the difficulties in the intracellular delivery to specific tissues where they silence the target genes. There have been many efforts to develop suitable, safe and effective siRNA delivery systems in the past decades. These efforts specifically aimed to protect siRNA from serum nucleases and deliver it to an intracellular region in the desired target cells. In this context, one of the new and popular approaches is nanovehicle-mediated siRNA delivery systems. Objective: Here, the authors reviewed and highlighted the recent advances in this exciting and fast growing field to help in the development of effective therapeutic tools in controlling human diseases. Methods: A literature search was conducted from electronic databases such as Pubmed and Google scholar including original articles and review articles. Conclusion: siRNA delivery systems potentially may be used in future medicine, particularly for untreatable or poorly treated diseases. As we learn more about these delivery systems, we can better use the tremendous opportunities provided by siRNA-based therapeutics. The results of ongoing clinical trials will play an important role in determining whether siRNA-based drugs can be considered as a new class of drugs.

Background: Prostatitis is a recurrent urinary infection in males and is often difficult to cure. The aim of the study was to examine whether anti-inflammatory effects of enhanced drainage of prostatic secretions, obtained through two months treatment with a proteolytic enzyme mucoactive (PEM) compound (Serrazyme and other constituents), influenced qualitative or quantitative expressions of bacterial growth in seminal cultures. Method: 450 patients with prostatitis syndromes were randomized either to PEM therapy (intervention group) or to no treatment group. All patients were followed at the end of a 2-month PEM continuous treatment period (T2) and further two months after withdrawal (T4). Results: After treatment, 15 out of 107 (14.1%) patients with Chronic Bacterial Prostatitis (CBP) showed negative seminal cultures, while in patients with cat NIH-IIIA prostatitis seminal cultures became positive in 33.3% cases with low bacteriospermia. After two months from withdrawal, although among CBP patients the total number of isolates and colony forming units (CFU) counts showed not significant changes compared to matched-values observed at T2, microbial parameters varied significantly among inflammatory prostatitis patients. Conclusion: The results of the present study showed that 2 months of treatment with PEM, decreasing bacterial adherence and inflammatory prostatitis, reveals a subgroup of apparent inflammation associated with infection that microbial biofilms likely mask in inflammatory prostatitis patients.

Background: Osteogenesis imperfecta is a rare metabolic disorder associated with reduced mineralization of bone and corresponds to increased fracture risk. We carried out the present network meta-analysis comparing all the medical interventions for osteogenesis imperfecta. Method: Electronic databases were searched for randomized controlled clinical trials evaluating the use of drugs in patients with osteogenesis imperfecta. Percent change in BMD was the primary and fracture risk reduction and adverse events were the secondary outcome measures. The weighted mean difference was the pooled estimate for primary outcome and odds ratio with 95% confidence interval for the secondary outcome measures. Direct and mixed treatment comparisons between the interventions were carried out by inverse heterogeneity model. Sub-group analyses were carried out on children, adults and within bisphosphonate groups. The trial sequential analysis was carried out for the comparison of oral bisphosphonates with placebo. Results: A total of 16 studies were included evaluating oral and intravenous bisphosphonates, teriparatide, anti-sclerostin antibody, high dose vitamin D and recombinant growth hormone (rGH) combined with intravenous bisphosphonates. Oral bisphosphonates and teriparatide were observed with a statistically significant increase in BMD compared to placebo. Also, only oral bisphosphonates were associated with significant reduction in the fracture risk but when the alpha error was adjusted for the information accrued till date as well as when the results of a trial were excluded, no significant difference was observed. Either low or very low quality was observed for pooled estimates of the key comparisons. Conclusion: Oral bisphosphonates and teriparatide significantly increase BMD but are not associated with fracture risk reduction. Of the available interventions, oral bisphosphonates could perform better than others in osteogenesis imperfecta. This evidence should be considered preliminary and may change with future head-to-head clinical trials.

Background: Drug development for rare diseases is challenging because it is difficult to obtain relevant data from very few patients. It must be informative to grasp current status of clinical trials for drug development in rare diseases. Objective: Clinical trials in rare diseases are to be outlined and compared among the US, EU and Japan. Method: ClinicalTrials.gov (NCT, National Clinical Trial), EU Clinical Trials Register (EUCTR) and the Japan Primary Registries Network (JPRN) were analyzed. Clinical trials involving information on rare diseases and drugs were extracted by text-mining, based on the diseases and drugs derived from Orphanet and DrugBank, respectively. Results: In total, 28,526 clinical trials were extracted, which studied 1,535 rare diseases and 1,539 drugs. NCT had the largest number of trials, involving 1,252 diseases and 1,332 drugs. EUCTR and JPRN also had registry-specific diseases (250 and 22, respectively) and drugs (172 and 29, respectively) that should not be missed. Among the 1,535 rare diseases, most diseases were studied in only a limited number of trials; 70% of diseases were studied in fewer than 10 trials, and 28% were studied in only one. Additionally, most studied rare diseases were cancer-related ones. Conclusion: This study has revealed the characteristics of the clinical trials in rare diseases among the US, EU and Japan. The number of trials for rare diseases was limited especially for non-cancerrelated ones. This information could contribute to drug development such as drug-repositioning in rare diseases.