a. Advanced heart failure is an incurable ailment that manifeststhrough cardiac dysfunction. The condition is responsible forexcessive mortality, morbidity, medical care costs andhospitalizations throughout the world (Jessup et al., 2011). Genetherapy is highly appropriate for congestive heart failure since thelatter is an acquired polygenic condition (Kawase, Ladage, &Hajjar, 2011). Furthermore, gene-based treatments have been enhancedby recent improvements in gene transfer technology along with greaterunderstanding of the molecular characteristics of myocardialdysfunction (Kawase et al., 2011).
b. The viral vector (AAV1) is used to infuse the SERCA2a gene torestore crucial enzymes in patients with chronic heart failure(Jessup et al., 2011). Consequently, several outcomes will beobtained such as a reduction in natriuretic peptide levels andadverse symptoms of cardiac dysfunction (Jessup et al., 2011).Furthermore, cells will be targeted through transductional andtranscriptional processes whereby the latter method involves theaction of cardiac specific promoters (Tilemann, Ishikawa, Weber, &Hajjar, 2012). Notably, the former method drives the exclusiveexpression of the transgene into the heart (Tilemann et al., 2012).
c. The randomizedtrial comprised of a dose-ranging, parallel-group,placebo-controlled, and double-blind study featuring 39 patients(Jessup et al., 2011). All participants received AAV1/SERCA2a throughintra-coronary infusion administered at three dose levels over a yearwith a two-year follow-up via telephone (Jessup et al., 2011).Consequently, intolerance or comorbidities can be cited to interpretthe results that showed a lower likelihood of β-blocker usage amongthe groups that had received higher doses of AAV1/SERCA2a (Jessup etal., 2011).
d. I wouldrecommend the company to continue making improvements to the study bytesting more people. Inevitably, using only 39 patients limits thefindings on the effects of the delivered gene (Jessup et al., 2011).Therefore, the company must conduct larger trials to examine thetherapy’s capability of treating chronic heart failure.
Jessup, M. et al. (2011). Calcium upregulation by percutaneousadministration of gene therapy in cardiac disease (CUPID): A phase 2trial of intracoronary gene therapy of sarcoplasmic reticulumCa2+-ATPase in patients with advanced heart failure. Circulation,124(3), 304-313. doi:10.1161/CIRCULATIONAHA.111.022889
Kawase, Y., Ladage, D., & Hajjar, R. J. (2011). Rescuing thefailing heart by targeted gene transfer. Journal of the AmericanCollege of Cardiology, 57(10), 1169-1180.doi:10.1016/j.jacc.2010.11.023
Tilemann, L., Ishikawa, K., Weber, T., & Hajjar, R. J. (2012).Gene therapy for heart failure. Circulation Research, 110(5),777-793. doi:10.1161/CIRCRESAHA.111.252981