When the World Health Organization (WHO) tallied up the total price tag for immunization programs over the next decade in the world’s 72 poorest countries, the surprise wasn’t the total–$35 billion–but that fully two-thirds of this sum would be spent not on the drugs but on the delivery systems and the staff overhead to administer them. Syringes are cheap, costing pennies apiece, but they require trained staff. Inhalers are easier and safer to administer–but far more expensive to buy.
Now comes a simple new piece of technology: a four-cent inhaler that administers drugs without the moving parts or aerosols used in traditional inhalers, which have as many as 20 moving parts and cost up to 40 cents apiece. The advance comes as more and more pharmaceutical companies–spurred in part by the Kyoto Protocol, which banned propellants used in traditional aerosol inhalers–are developing dry-powder inhalable versions of everything from insulin to flu vaccines.
To make their inhaler cheaper, engineers at Cambridge Consultants, of Cambridge, England, and Boston, focused on its internal shape. When a user inhales, a kind of miniature tornado forms inside the device, lifting a powdered drug into the air. The company’s engineers closed the bottom of the cyclone to promote recirculation, giving the drug more chance to become aerosolized and propelled deeply into the lungs. The company says that its own laboratory tests show that the gadget, despite having no moving parts, is actually significantly more efficient in delivering usable drugs than traditional inhalers are. “Every formulation we’ve placed in it so far from the public domain, we see in excess of a 40 percent performance improvement,” says Brian Barney, head of drug delivery for Cambridge Consultants.
A user must simply unfold the inhaler, which pierces a foil pouch that holds dry powder, and breathe in. That means patients don’t need much staff help, and health-care workers can oversee more patients while avoiding the hazards of needle sticks. The company says that five pharmaceutical and drug-delivery companies are at some stage of doing feasibility studies, in which they test drug formulations with the device. Early results are expected in February. If a pharmaceutical company does decide to license the gadget, it would have to conduct clinical trials–a process that would take between three and four years. In the case of a flu vaccine, though, this process could be fast-tracked and completed within a year.
Donald P. Francis, a consultant to the WHO and cofounder of Global Solutions for Infectious Diseases, a nonprofit that develops low-cost vaccines, says that a cheap inhaler could be particularly beneficial in the developing world. “It’s a great idea,” he says. “Everyone in the field dreams of a future with these kinds of simple low-cost vaccine delivery systems. Moving to a needle-free model is a goal most of us share. Imagine being able to distribute an inhalant vaccine simply through the post-office system, in a format that anyone in the household can be trained to use. It would be a wonderful switch over.”
But Francis is also cautious: “To test such a product on a mass level and get it to the point where it can be shown to convincingly work as well as a needle-delivered vaccine is a costly investment, and not one that for-profit drug companies have shown a lot of interest in.” What is clear is the cost benefit. For example, the WHO says that current injectable inactive flu vaccines cost between $3 and $7 per dose.
No dry-powder inhalable flu vaccine is on the market, but if this $3-to-$7 price were to hold for inhalable powders, a cheaper inhaler could shave 5 to 10 percent from the cost of each dose, just from the delivery system alone. And a far larger additional savings would come from the reduced need for trained staff who would otherwise have to administer individual syringe injections.
While Cambridge Consultants says it can’t name the pharmaceutical companies it is working with, there is clearly widespread industry work on dry-powder versions of many drugs and vaccines. For example, Pfizer is making inhalable insulin, and Alkermes and Lilly are working together to develop both inhaled insulin and an inhaled osteoporosis drug. At least five companies are developing inhalable flu vaccines, prompted by billions of dollars in government investment in preventing an avian-flu pandemic. Glaxo Smith Kline already has an inhalable flu treatment–Relenza–on the market. “This area is absolutely booming,” Barney says.
Marie-Paule Kieny, director of the WHO’s Initiative for Vaccine Research, says the WHO is hoping that a number of new technologies, including powders, nasal sprays, and patches, will be available over the next decade. “A simple and cheap device to permit the delivery of influenza vaccines by inhalation could potentially contribute significantly to mass immunization, particularly in the event of a pandemic,” she says.