Authors' objectives: Our goal was to assess the clinical effectiveness, cost effectiveness and safety of FreeStyle Libre for individuals with type 1 and 2 DM.

Authors' results and conclusions: We included two randomized controlled trials (RCTs) in the review. These studies compared FreeStyle Libre to SMBG. Also, we found several publications investigating the accuracy of the device, however, the study designs of these studies (single arm) did not meet the inclusion criteria of this evaluation and, although we compiled them for information, they were excluded from the synthesis. The information derived from these single arm studies are potentially important to validate the sensitivity and specificity estimates of FreeStyle Libre. In addition, we found other European assessments conducted in the past 6 to 8 months. The included RCTs reported data on middle aged adults from European countries with type 1 and 2 DM at 6 months post intervention. We rated the studies’ risk of bias as unclear to high risk. Main findings from these trials are that FreeStyle Libre may slightly improve treatment satisfaction, time spent with glucose in range 3.9 to 10 mmol/L, number of nocturnal events with glucose levels 13.0 mmol/L in comparison to SMBG. FreeStyle Libre lead to little or no difference in quality of life and HbA1c level in comparison to SMBG. The evidence is uncertain about whether FreeStyle Libre leads to an improvement in time and events with glucose

Authors' recommendations: Suggested research priorities: Independent research for FreeStyle Libre will be important. Diabetes affects the life of children, adolescents and their caregivers in many ways, as well as pregnant women. Independent research including these groups is warranted. The clinical effectiveness of FreeStyle Libre needs to be investigated in different conditions, for example, among individuals with poor self-monitoring adherence, newly diagnosed, impaired awareness of hypoglycaemia, and in addition to training and education components. FreeStyle Libre compared to other continuous monitoring systems is warranted. Pain is a major determinant of diabetes treatment adherence, especially for children, and it should be included as an individual outcome in future trials. Future trials should include longer term follow up and quality of life outcome assessments at various points to inform improved clinical and cost effectiveness modelling.

Authors' methods: We conducted a systematic review according to standard methods to summarise the evidence. The study populations were insulin treated individuals with Type 1 or 2 DM, the intervention was FreeStyle Libre, and the outcomes were HbA1c, hypo and hyperglycaemia, quality of life, patient satisfaction, pain, and adverse events. We searched databases, trial registries, health technology assessment agencies websites and grey literature from inception to January 2017 with no language restrictions. Two reviewers independently screened the titles and abstracts of all records identified by searches, discussed any discrepancies and solved them by consensus. We obtained full text copies of all studies deemed potentially relevant and the same two reviewers independently assessed these for inclusion; solving any disagreements by consensus. One reviewer extracted data relating to study details, participants, intervention, and comparator, using a piloted, standard data extraction form. A second reviewer checked data extraction and any disagreements we resolved by consensus. The assessment of the methodological quality of each included study was based on the Cochrane Collaboration risk of bias tool. Quality assessment of evidence was carried out independently by two reviewers. We solved any disagreements by consensus. Meta-analysis was considered a suitable analysis for the data identified, despite heterogeneity. For some outcomes we employed a narrative synthesis. Assessment of cost effectiveness: We assessed the cost-effectiveness estimates provided by the submitter of FreeStyle Libre compared to self-monitoring blood glucose (SMBG) for individuals with type 1 and 2 DM. The submitter used a commercially available cost-effectiveness model, IMS CORE diabetes model (IMS CDM) for this assessment. The model is internet based, with a Markov application, for individuals >18 years. The interactive simulation predicts the long-term health outcomes and costs associated with the management of type 1 and 2 DM. The model consist of 17 sub-models designed to simulate diabetes related complications, nonspecific mortality, and costs over time. As the model simulates individual patients over time, it updates risk factors and complications to account for disease progression. However, this model received from the submitter, lacks transparency, and made it difficult to gain a firm understanding of the factors that determine how patients progress through the model, assumptions and parameters effect outcomes and to assess the validity of the model. Because the Norwegian Institute of Public Health did not have complete access to the model, it was not possible to perform a full assessment of the model or to modify underlying assumptions and parameters in order to independently assess the impact on reported results. Furthermore, the documentation package did not include any sensitivity analysis, which is essential for considering the validity and robustness of results from economic evaluations.

Project Status: Completed

Year Published: 2017

URL for published report: https://www.fhi.no/en/publ/2017/freestyle-libre-systemet-for-egenmaling-av-blodsukker-en-hurtigmetodevurder/

English language abstract: An English language summary is available

Publication Type: Full HTA

Country: Norway

Organisation Name: Norwegian Institute of Public Health

Contact Address: P.O. Box 222 Skoyen, N-0123, Oslo