Fenofibrate and Telmisartan in the Management of Abdominal Aortic Aneurysm

OBJECTIVE

This mini-review provides the rationale and updated progress for ongoing randomized controlled trials assessing fenofibrate and telmisartan efficacy to limit abdominal aortic aneurysm (AAA) growth.

METHODS/RESULTS

There remains an urgent need to identify a drug therapy that will limit AAA growth. Data from preclinical and human studies indicate that fenofibrate and telmisartan have the potential to slow aortic destruction. Fenofibrate has been shown to reduce serum and tissue levels of the proinflammatory protein osteopontin, as well as reducing macrophage recruitment to the aortic wall, both of which are integral processes in the development and progression of AAAs. Telmisartan acts via blockade of the angiotensin II receptor, type 1, and also as a peroxisome proliferator-activated receptor gamma agonist. In turn, this inhibits the production of a range of biomarkers associated with AAA progression, including transforming growth factor-beta one, osteoprotegerin, osteopontin and matrix metalloproteinase- 9. Based on these findings, there are currently three randomized controlled trials assessing both fenofibrate and telmisartan as potential interventions to limit aneurysm growth in AAA patients.

CONCLUSION

Fenofibrate and telmisartan have potential as repurposed medications to limit AAA growth, and randomized trials for further assessment in AAA patients are ongoing.

Reversing activity of cancer associated fibroblast for staged glycolipid micelles against internal breast tumor cells

Rationale: Nano-carrier based combinational therapies for tumor cells hold great potential to improve the outcomes of patients. However, cancer associated fibroblasts (CAFs) in desmoplastic tumors and the derived pathological tumor stroma severely impede the access and sensitibity of tumor cells to antitumor therapies.

Methods: Glycolipid-based polymeric micelles (GLPM) were developed to encapsulate an angiotensin II receptor I inhibitor (telmisartan, Tel) and a cytotoxic drug (doxorubicin, DOX) respectively, which could exert combinational antitumor efficacy by reprogramming tumor microenvironment to expose the vulnerability of internal tumor cells.

Results: As demonstrated, α-SMA positive CAFs significantly decreased after the pre-administration of GLPM/Tel in vitro, which accordingly inhibited the secretion of the CAFs derived stroma. The tumor vessels were further decompressed as a result of the alleviated solid stress inside the tumor masses, which promoted more intratumoral drug delivery and penetration. Ultimately, staged administration of the combined GLPM/Tel and GLPM/DOX at the screened molar ratio not only inhibited the stroma continuously, but also achieved a synergistic antitumor effect through the apoptosis-related peroxisome proliferator-activated receptor-gamma (PPAR-γ) pathway.

Conclusion: In summary, the strategy of suppressing tumor stroma for subsequent combinational therapies against internal breast tumor cells could provide avenues for management of intractable desmoplastic tumors.

The Use of Telmisartan and the Incidence of Cancer

BACKGROUND

A meta-analysis reported an 8% increased risk of cancer with the use of angiotensin receptor blockers (ARBs), but subsequent meta-analyses and observational studies did not confirm this risk. However, telmisartan comprised 85% of the data in the original meta-analysis. Thus, the objective of this study was to determine whether the use of telmisartan, compared with other ARBs, is associated with an increased risk of cancer.

METHODS

We used the United Kingdom Clinical Practice Research Datalink to assemble a cohort of all patients newly treated with ARBs between 2000 and 2008, and followed until December 2010. Time-dependent cox proportional hazards models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) of cancer associated with telmisartan, compared with other ARBs, adjusted for potential confounders. Secondary analyses assessed the risk with each of the 4 most common cancers (lung, breast, prostate, colorectal).

RESULTS

The cohort consisted of 62,109 new ARB users, which included 3,438 telmisartan and 58,671 other ARB users. Compared with other ARBs, telmisartan use was not associated with an increased risk of cancer overall (16.3 vs. 15.0 per 1,000 person-years, respectively; adjusted HR: 0.93, 95% CI: 0.81-1.06) or by cancer site (lung, HR: 0.91, 95% CI: 0.55-1.51; breast, HR: 1.28, 95% CI: 0.90-1.82; prostate, HR: 0.79, 95% CI: 0.53-1.18; colorectal, HR: 1.41, 95% CI 0.95-2.10).

CONCLUSIONS

Compared with other ARBs, telmisartan is not associated with an increased risk of cancer. This study provides reassurance as to the short-term safety of telmisartan.