The Budget Impact of Monoclonal Antibodies Used to Treat Metastatic Colorectal Cancer in Minas Gerais, Brazil.

INTRODUCTION: Biological medicines have increased the cost of cancer treatments, which also raises concerns about sustainability. In Brazil, three monoclonal antibodies (mAbs)-bevacizumab, cetuximab, and panitumumab-are indicated for the treatment of metastatic colorectal cancer (mCRC) but not currently funded by the Unified Health System (SUS). However, successful litigation has led to funding in some cases. OBJECTIVE: Our objective was to evaluate the budgetary impact of including the mAbs bevacizumab, cetuximab, and panitumumab in standard chemotherapy for the treatment of mCRC within the SUS of Minas Gerais (MG), Brazil. METHOD: A budget impact analysis of incorporating mAbs as first-line treatment of mCRC in MG was explored. The perspective taken was that of the Brazilian SUS, and a 5-year time horizon was applied. Data were collected from lawsuits undertaken between January 2009 and December 2016, and the model was populated with data from national databases and published sources. Costs are expressed in $US. RESULTS: In total, 351 lawsuits resulted in funding for first-line treatment with mAbs for mCRC. The three alternative scenarios analyzed resulted in cost increases of 348-395% compared with the reference scenario. The use of panitumumab had a budgetary impact of $US103,360,980 compared with the reference scenario over a 5-year time horizon, and bevacizumab and cetuximab had budgetary impacts of $US111,334,890 and 113,772,870, respectively. The use of the anti-epidermal growth factor receptor (EGFR) mAbs (cetuximab and panitumumab) is restricted to the approximately 41% of patients with KRAS mutations, so the best cost alternative for incorporation would be the combination of panitumumab and bevacizumab, with a cost of approximately $US106 million. CONCLUSION: These results highlight the appreciable costs for incorporating bevacizumab, cetuximab, and panitumumab into the SUS. Appreciable discounts are likely to be necessary before incorporation of these mAbs is approved.

Comparative Effectiveness and Safety of Monoclonal Antibodies (Bevacizumab, Cetuximab, and Panitumumab) in Combination with Chemotherapy for Metastatic Colorectal Cancer: A Systematic Review and Meta-Analysis.

BACKGROUND: The last decade has seen the increasing use of biological medicines in combination with chemotherapy containing 5-fluorouracil/oxaliplatin or irinotecan for the treatment of metastatic colorectal cancer (mCRC). These combinations have resulted in increased progression-free survival (PFS) in patients with mCRC; however, there are remaining concerns over the extent of their effect on overall survival (OS). Published studies to date suggest no major differences between the three currently available monoclonal antibodies (MoAbs); however, there are differences in costs. In addition, there is rising litigation in Brazil in order to access these medicines as they are currently not reimbursed. OBJECTIVE: The aim was to investigate the comparative effectiveness and safety of three MoAbs (bevacizumab, cetuximab and panitumumab) associated with fluoropyrimidine-based chemotherapy regimens and compared to fluoropyrimidine-based chemotherapy alone in patients with mCRC, through an updated systematic review and meta-analysis of concurrent or non-concurrent observational cohort studies, to guide authorities and the judiciary. METHOD: A systematic review and meta-analysis was performed based on cohort studies published in databases up to November 2017. Effectiveness measures included OS, PFS, post-progression survival (PPS), Response Evaluation Criteria In Solid Tumors (RECIST), response rate, metastasectomy and safety. The methodological quality of the studies was also evaluated. RESULTS: A total of 21 observational cohort studies were included. There were statistically significant and clinically relevant benefits in patients treated with bevacizumab versus no bevacizumab mainly around OS, PFS, PPS and the metastasectomy rate, but not for the disease control rates. However, there was an increase in treatment-related toxicities and concerns with the heterogeneity of the studies. CONCLUSION: The results pointed to an advantage in favor of bevacizumab for OS, PFS, PPS, and metastasectomy. Although this advantage may be considered clinically modest, bevacizumab represents a hope for increased survival and a chance of metastasectomy for patients with mCRC. However, there are serious adverse events associated with its use, especially severe hypertension and gastrointestinal perforation, that need to be considered.

The inhibitory potential of the condensed-tannin-rich fraction of Plathymenia reticulata Benth. (Fabaceae) against Bothrops atrox envenomation.

ETHNOPHARMACOLOGICAL RELEVANCE: Ethnobotanical studies have shown that Plathymenia reticulata Benth. (Fabaceae) has been widely used in cases of snake envenomation, particularly in Northern Brazil. In light of this, the aim of this study was to evaluate the inhibitory potential of the condensed-tannin-rich fraction obtained from the bark of P. reticulata against the main biological activities induced by Bothrops atrox venom (BaV). MATERIALS AND METHODS: The chemical composition of the aqueous extract of P. reticulata (AEPr) was first investigated by thin-layer chromatography (TLC) and the extract was then fractionated by column chromatography on Sephadex LH-20. This yielded five main fractions (Pr1, Pr2, Pr3, Pr4 and Pr5), which were analyzed by colorimetry to determine their concentrations of total phenolics, total tannins and condensed tannins and to assess their potential for blocking the phospholipase activity of BaV. The Pr5 fraction was defined as the fraction rich in condensed tannins (CTPr), and its inhibitory potential against the activities of the venom was evaluated. CTPr was evaluated in different in vivo and in vitro experimental protocols. The in vivo protocols consisted of (1) pre-incubation (venom:CTPr, w/w), (2) pre-treatment (orally administered) and (3) post-treatment (orally administered) to evaluate the effect on the hemorrhagic and edematogenic activities of BaV; in the in vitro protocol the effect on phospholipase and coagulant activity using pre-incubation in both tests was evaluated. RESULTS: There was statistically significant inhibition (p<0.05) of hemorrhagic activity by CTPr when the pre-incubation protocol was used [55% (1:5, w/w) and 74% (1:10, w/w)] and when pre-treatment with doses of 50 and 100mg/kg was used (19% and 13%, respectively). However, for the concentrations tested, there was no statistically significant inhibition in the group subjected to post-treatment administered orally. CTPr blocked 100% of phospholipase activity and 63.3% (1:10, w/w) of coagulant activity when it was pre-incubated with BaV. There was a statistically significant reduction (p<0.05) in edema induced by BaV in the oral protocols. Maximum inhibition was 95% (pre-treatment). CONCLUSION: Our findings indicate that CTPr could be a good source of natural inhibitors of the components of snake venom responsible for inducing local inflammation.

Mercurial exposure of residents of Santarém and Oriximiná cities (Pará, Brazil) through fish consumption.

A survey of the mercurial exposure of residents of Santarém and Oriximiná showed a differential mercurial impregnation between men and women. At the level of both cities, the mean hair mercury concentrations were 1.5 ± 0.5 (90th and 95th percentiles: 2.8 and 4.3) and 2.52 ± 0.09 µg g Hg/g (90th and 95th percentiles: 4.7 and 8.1) for women and men, respectively. The mercurial contamination appeared significantly closely linked to the daily amount of consumed fish. Carnivore species pescada branca (Plagioscion squamosissimus) and apapá (Pellona castelnaeana) and non-carnivore species pacú (Mylossoma duriventre) and aracú (Schizodon fasciatus) were consumed by 22, 19, 55 and 25% of people, respectively, and the mean mercury concentrations within fish flesh were 1.44 ± 0.11, 1.66 ± 0.19, 0.48 ± 0.09 and 0.49 ± 0.06 µg/g dry weight, respectively. Men aged above 35 were significantly more contaminated than those below. The mean hair concentrations of men were 5.20 ± 1.25 and 1.50 ± 0.22 µg/g, for those aged above 35 and below, respectively. The probability for women of childbearing age from both cities to present a hair mercury concentration above 1 µg Hg/g (corresponding to the US Environmental Protection Agency reference dose) was equal to 0.30 (95% confidence interval of 0.24-0.36). The probability of hair mercury concentration to be above the lowest observable adverse effect level (LOAEL) (0.3 µg Hg/g) was equal to 0.79 (95% confidence interval: 0.73-0.86).