Forms of the drug - used to treat cancer pain - are often imported illegally from Chinese laboratories and sold to users via the dark web.
The reduction follows the Government's strict introduction of a blanket ban on new psychoactive substances.
He told the BBC: 'The UK government has nowhere left to hide.
Niamh Eastwood, executive director of drug policy reform group Release, says the government's position on DCRs also makes it hard to tackle the problem of drug-related deaths. They are responsible for vulnerable people dying in droves'.
While cocaine deaths rose by almost a fifth past year, deaths involving other opiates decreased, and a statistically significant fall was seen in incidents involving new psychoactive substances.
Following a series of deaths in northern England in April 2017, Public Health England warned heroin users to test drugs before using so as to not mistake heroin for fentanyl.
ONS health analysis statistician Ellie Osborn said: "The figures published today show that the level of drug poisoning deaths in 2017 remained stable".
David Jamieson, the West Midlands Police & Crime Commissioner, said these figures on drug-related deaths are "tragic".
There were 75 fatalities linked to the opioid a year ago, an increase of 29 per cent from 2016 when there were 58.
The drug has been found mixed with heroin, causing accidental overdoses in users.
Carfentanyl, a synthetic opiate which is more powerful than fentanyl, was mentioned on death certificates for the first time in 2017 and accounted for 27 deaths. The drug can up to 100 times stronger than heroin and is sometimes prescribed as a painkiller for the terminally ill.
Security Minister Ben Wallace warned in May that the United Kingdom was "fast becoming the biggest consumer of cocaine in Europe".
The rate of drug-related deaths has soared since the Conservative Party came to power in 2010, with a 30 per cent increase in heroin/morphine deaths during this period, and a staggering 200 per cent increase in cocaine-related deaths. London had the lowest number of deaths.
Despite exceeding the five-year average, the latest death figures were below the number registered during the same period in 2017 and 2016.
However, the overall death rate remains mostly unchanged, having risen from just 65.8 per million past year.
"Generally speaking, the system is less and less fit for goal", she said.
Short-term physiological effects of cocaine use include constricted blood vessels, dilated pupils, increased body temperature, high heart rate and a spike in blood pressure, according to the US National Institute on Drug Abuse.
Parenting in the age of Alexa and her ilk
After you enable the feature, Alexa will notify you once it learns the answer to a question you've asked previously. Probably too late and when you've forgotten why you were asking or found out another way.