The UK’s competition watchdog has imposed fines of more than £100m on the pharmaceutical company Advanz and its former private equity owners after it was found to have inflated the price of its thyroid tablets by up to 6,000%. An investigation by the Competition and Markets Authority (CMA) found that the private-equity backed pharmaceutical company charged “excessive and unfair prices” for liothyronine tablets, which are used to treat thyroid hormone deficiency. Advanz took advantage of limited competition in the market from 2007 to bring in sustained price hikes for the drug, often used by patients with depression and fatigue, of more than 6,000% in the space of 10 years, according to the investigation. The CMA said that between 2007 and 2017, the price paid by the NHS for liothyronine tablets rose from £4.46 to £258.19, a rise of almost 6,000%, while production costs remained broadly stable. Repeated price increases led NHS spending on the tablets to soar from £600,000 in 2006, before the price increase strategy was implemented, to more than £2.3m by 2009 and as much as £30m by 2016. The tablets were placed on the NHS “drop list” in July 2015, which meant GPs could no longer prescribe them, causing many people who relied on the drug to face the prospect of having their treatment stopped or having to purchase it at their own expense. Patients told the Guardian they were left with no option but to pay private doctors for prescriptions, and forced to hunt for cheaper tablets over the internet, buying the medication from online pharmacies and foreign suppliers without knowing whether the tablets being sold were genuine. The CMA said this was “particularly concerning” because many patients do not respond well to the main treatment for hypothyroidism – levothyroxine tablets – and rely on liothyronine to treat their extreme fatigue and depression. Advanz will be fined almost £41m, and two of its former private equity owners – Hg Capital and Cinven – will pay penalties of £8.6m and £51.9m respectively. Dr Andrea Coscelli, the CMA’s chief executive, said: “Advanz’s decision to ratchet up the price of liothyronine tablets and impose excessive and unfair prices for over eight years came at a huge cost to the NHS, and ultimately to UK taxpayers. “But that wasn’t all. It also meant that people dealing with depression and extreme fatigue, as a result of their thyroid conditions, were told they could not continue to receive the most effective treatment for them due its increased price.” He said the CMA’s £100m fine and other work in the pharmaceutical sector would send “a clear message that breaking the law has serious consequences”. The CMA imposed fines of more than £260m two weeks ago on pharmaceutical companies that had overcharged the NHS for almost a decade for hydrocortisone tablets, which tens of thousands of people rely on to treat adrenal insufficiency. Its latest intervention against Advanz follows a five-year investigation that began in October 2016 and involved multiple companies. The company was originally two separate entities, Mercury Pharma Group and Adipharm. London-based private equity group Hg Capital bought Mercury for £179m in 2009 and sold it to fellow buyout house Cinven for £465m in 2012. Cinven had bought family-owned niche pharmaceuticals business Adipharm that same year, for £367m, and subsequently merged the two businesses. In 2015, Cinven sold the combined entity to Concordia Healthcare, a Canadian company listed on the Toronto stock exchange, in a £2.3bn deal. In 2018, a year after the CMA first accused the company of abusing its position, Concordia changed its name to Advanz Pharma. It later de-listed from the stock exchange, underwent a financial restructuring, and was bought in 2021 by Copenhagen-based Nordic Capital for £605m.