Drugs Becoming Generics-The Impact of Genericization on the Market Performance of Antihypertensive Active Pharmaceutical Ingredients

Impact of ramipril nitroso-metabolites on cancer incidence - in silico and in vitro safety evaluation

Background

Angiotensin-converting enzyme inhibitors (ACE-I) and their pharmacologically related sartans have been associated with an increased cancer incidence in several clinical observations. In 2018, sartans were revealed as being significantly contaminated with nitrosamines. Nitrosamines are potent human mutagens that can be formed ex vivo and, more concerningly, also in vivo from nitrosatable drug precursors. Their formation in sartans may justify the reported cancer risk and, by analogy, this may also apply to ACE-Is.

Materials and methods

We investigated a commonly used ACE-I, ramipril (RAM). We checked its susceptibility to in vivo interaction with nitrite, potentially resulting in the generation of mutagenic N-nitrosamines. To that end, in silico simulation of mutagenicity of RAM nitroso-derivatives was performed using VEGA-GUI software. Then, the Nitrosation Assay Procedure was conducted which served as a model of endogenous reaction. The resulting post-nitrosation mixtures were subjected to a bacterial reverse mutation test employing Salmonella typhimurium strains TA98 and TA100 with and without metabolic activation.

Results

Our results showed that studied samples did not induce point mutations in the test bacteria, regardless of the catalytic cytochrome activity.

Conclusion

We concluded that RAM endogenous nitrosation is not the reason for increased cancer incidence. However, other ACE-Is must be verified in a similar manner.

In silico and in vitro screening for carcinogenic potential of angiotensin-converting enzyme inhibitors and their degradation impurities

According to some clinical observations, the use of angiotensin-converting enzyme inhibitors (ACEI) may be associated with an increased risk of cancer. The aim of the present study was to screen for the potential carcinogenicity, mutagenicity and genotoxicity of these drugs using in silico methodology. Delapril, enalapril, imidapril, lisinopril, moexipril, perindopril, ramipril, trandolapril, spirapril were thereby analyzed. In parallel, the corresponding degradation impurities, the diketopiperazine (DKP) derivatives, were also investigated. (Q)SAR computer software (VEGA-GUI and Lazar), available in the public domain, was employed. The obtained predictions suggested that none of the compounds tested (from the group of ACE-Is and DKPs) was mutagenic. Moreover, none of the ACE-Is was carcinogenic. The reliability of these predictions was high to moderate. In contrast, in the DKP group, ramipril-DKP and trandolapril-DKP were found to be potentially carcinogenic, but the reliability of this prediction was low. As for the genotoxicity screening, all compounds tested (ACE-I and DKP) were predicted to be active and genotoxic, with moexipril, ramipril, spirapril, and all DKP derivatives within the highest risk group. They were prioritized for experimental verification studies to confirm or exclude their toxic activity. On the other hand, the lowest risk of carcinogenicity was assigned to imidapril and its DKP. Then, a follow-up in vitro micronucleus assay for ramipril was performed. It showed that this drug was genotoxic via aneugenic activity, but only at concentrations exceeding real-life levels. At concentrations found in human blood after standard dose, ramipril was not genotoxic in vitro. Therefore, ramipril was considered safe for human use with a standard dosing regimen. The other compounds of concern (spirapril, moexipril and all DKP derivatives) should be subjected to analogous in vitro studies. We also concluded that the adopted in silico software was applicable for ACE-I toxicity prediction.

Trends in sales of antidepressants in Brazil from 2014 to 2020: A time trend analysis with joinpoint regression

BACKGROUND

This study aimed to investigate the trends in antidepressants sales in Brazil.

METHODS

We performed a joinpoint analysis of antidepressants sales in Brazil from 2014 to 2020, recorded in the Brazilian National Controlled Products Management System. The primary outcomes were the defined daily dose per 1000 inhabitants per day (DID) and the market shares for each antidepressant per year. We used joinpoint regression to assess the changes in antidepressant consumption in DID to obtain the average annual percent change (AAPC) and 95 % confidence intervals (95 % CI). Changes in market shares were tested by chi-square trend test (p < 0.05 as significant).

RESULTS

From 2014 to 2020, 42,252,989 antidepressant sales were recorded in the system. Antidepressant sales increased from 13.7 to 33.6 DID in the period (AAPC: 15.7; 95 % CI: 13.0-18.4; p < 0.001); the largest increases were observed for serotonin reuptake inhibitors and 'other' antidepressants (including serotonin-norepinephrine reuptake inhibitors), whereas tricyclics remained steady. Escitalopram and sertraline were the most sold drugs. Market share of serotonin reuptake inhibitors decreased, particularly for paroxetine (13.1 % to 6.5 %; p = 0.016), while 'other' antidepressants' market share expanded from 21.9 % to 33.3 % (p = 0.027), especially for desvenlafaxine (2.9 % to 14.3 %; p < 0.001).

LIMITATIONS

The dataset does not include antidepressants dispensed in hospitals, public services, and compounding pharmacies, neither their therapeutic indications.

CONCLUSION

Sales of antidepressants significantly increased in Brazil from 2014 to 2020, which were mainly driven by higher prescriptions of serotonin reuptake inhibitors and 'other' antidepressants classes. Market share changes seem to be driven by novelty of products.