Linked wirelessly to the cloud, the gadgets are part of a medical “Internet of things” that promises improved adherence, or correct use of the medication, and better health outcomes. They may also hold the key to company profits in an era of increasingly tough competition.

Drugmakers believe giving patients and doctors the ability to check inhaler use in this way could be a big help in proving the value of their medicines to governments and insurers, though they need to tread carefully on data privacy.

GlaxoSmithKline (GSK), AstraZeneca (AZNCF), and Novartis (NVS) all are chasing the opportunity via deals with device firms including U.S.-based Propeller Health and Australian-listed Adherium, as well as technology players like Qualcomm (QCOM).

Over the past half century, inhalers have revolutionized care by delivering medicines directly into the lungs and avoiding the serious side effects seen with older oral drugs. But getting patients to take their medication correctly remains a challenge.

“Technique is critical. You might have the world’s best blockbuster drug in an inhaler, but if patients don’t use it properly they won’t get the benefits,” said Omar Usmani, a consultant physician at Imperial College London.

With asthma and chronic obstructive pulmonary disease (COPD) affecting about 500 million people worldwide, the opportunity is large, and reducing serious attacks by improving adherence could save $19 billion a year in U.S. health care costs alone, Goldman Sachs analysts estimated in a report last year.

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Usmani envisages a future of high-tech inhalers that not only record doses but also use gyroscopic and acoustic sensors to check medicine flow, while monitoring the environment for allergens such as pollen. All that data can be fed to remote computer servers known as the cloud.

It is an idea big drug companies have embraced enthusiastically, in the knowledge that they need to find new ways to sell their products as cheap generics undercut long-established brands.

The first generic copies of GSK’s Advair, the world’s biggest inhaler with worldwide sales of nearly $6 billion in 2015, are expected to reach the U.S. market next year.

“It’s a race to the starting line,” Propeller CEO David Van Sickle told Reuters, describing the current jockeying among leading pharmaceutical firms.

“Today, there is really no major respiratory pharma company that doesn’t have a program to add connectivity to their inhaled medicines.”

Next Level

The field is now at an inflection point. Some inhalers with clip-on sensors are already being supplied to patients, but the drug industry is about to take things to the next level.

Next month, AstraZeneca will start a yearlong U.S. clinical trial designed to improve adherence to long-term therapy in nearly 400 patients with COPD using Adherium’s smart inhaler.

If it works as hoped, it could have the same impact on improving clinical outcomes as a completely new medicine, according to Martin Olovsson, AstraZeneca’s head of respiratory inhalation.

“Many asthma and COPD patients are misusing their medicines, for various reasons—they forget to take them or they don’t understand how to take them properly—and the result of that is less than optimal outcomes,” he said. “This offers a chance to change that dramatically.”

Last year, a smaller study reported in the journal Lancet Respiratory Medicine already showed Adherium’s device increased adherence to preventative medication to 84% from 30% in New Zealand children with asthma.

Now, with bigger studies, drug companies plan to dig deeper.

“There is still quite a lot of work to be done to understand which type of patients will benefit most,” said Raj Sharma, director of respiratory science and delivery systems at GSK, which is also planning clinical trials.

GSK, the respiratory market world leader since launching the Ventolin inhaler in 1969, signed a deal last December for Propeller to develop a customized sensor for its next-generation Ellipta inhaler.

While current smart inhalers use a clip-on device to send data, Novartis, working with Qualcomm, aims to go a step further by developing the first inhaler with an integrated sensor, which it aims to launch in 2019.

Generic drugmakers are also moving into the space, with Britain’s Vectura, one of the companies behind generic Advair, signing a deal with Propeller in May and Teva acquiring smart inhaler firm Gecko Health last year.

Current add-on sensors cost between $10 and $30 to produce and last up to two years, according to Propeller’s Van Sickle, but the pharmaceutical industry plans to include them in deals struck with healthcare providers by promising overall savings due to fewer hospitalizations.

Usmani, the Imperial College consultant, believes proving the cost-effectiveness of a connected device is the key challenge for smart inhalers, along with reassuring patients that their medical records are secure.

Research by Usmani and colleagues suggests younger patients, familiar with online banking and digital apps, are broadly happy to engage but older patients are more cautious.