The pharmaceutical drug business is very risky; it takes a lot of money to research and develop compounds for use as medicines and there’s little guarantee that these will ever make it through the long and arduous approval process let alone be financially successful. Industry estimates report that it takes 7-10 years for a drug to come to market and only 1 in 3 approved drugs ever generate enough returns to offset the costs of prior failures. Pharmaceutical companies therefore strive to find a “blockbuster” billion dollar drug every few years to remain profitable.
The allergic field has been an area of medicine that companies have always found very commercial. After all, it is estimated that allergies & asthma strike 1 in 5 Americans and costs our healthcare system between $20-25 billion per year. That doesn’t include days of school and work missed due to these conditions. Many allergy treatments that used to be prescription are now available over-the-counter, so what are the newest medicines that are being developed for patients with allergies & asthma? I’ll try to cover some of these in this week’s blog.
First of all, what’s NOT likely to be developed for future use are new antihistamines. These medicines that help itching & drainage & sneezing have been around for many years, and second generation compounds like Claritin
®, Allegra
®, and Zyrtec
® are now available without a prescription. Epinastine, an antihistamine currently available in the U.S. as an eye drop was under development in pill form, but this has apparently now been abandoned. More research into histamine receptors in the body may uncover new therapeutic options, but since current available medicines help the vast majority of allergy sufferers, it doesn’t make economic sense for companies to sink millions of dollars into developing competitors.
Anti-leukotrienes are the newest category of allergy medications, and there are some advances that may be soon available in this area. Since both Claritin®
& Singulair®
are approved for allergy use and target different ways to control symptoms, it made sense to combine the two compounds for allergy use. However, it now appears that the two pharmaceutical companies that were exploring this possibility have now ended their joint venture after the FDA did not approve the drug. A leukotriene receptor blocker similar to Singulair®
is currently undergoing clinical trials. Called pranlukast (possible trade name Onon), it will compete with Singulair®
though how well it will do is unknown since Singulair®
will become generic later this year.
Combination medicines are also being developed in asthma. For a few years now we have had combination inhalers joining an inhaled steroid and beta-agonist (smooth-muscle relaxants that open the airways) together, including Advair®, Spiriva®, and Dulera®. Other similar combinations currently being studied include Flutiform® from SkyePharma and Relovair® from GlaxoSmithKline. There are additional combination inhalers using different non-steroidal anti-inflammatory agents with other long-acting bronchodilators being studied and may provide us better ways to treat asthmatics in the future.
For many years we have also had a number of nasal sprays to treat allergic rhinitis. Many of these are steroid-type medicines that can irritate the lining of the nose and cause occasional bleeding, so most sprays are in a water-based formula to minimize side effects. However, many patients find these wet, runny, and bad-tasting and have longed for an aerosol spray instead. QNASAL, a non-aqueous “dry” spray delivering beclomethasone (a steroid) via HFA (an environmentally friendly propellant is currently awaiting approval.
The antibody called Xolair
® (omalizumab) is already approved for use in severe asthmatics that also have allergies and can help these patients get their hypersensitivity reactions under control. Because of its cost (approximately $10,000 to $30,000 per year), its use has been limited to patients that require high doses & frequent steroids to control their symptoms. Because of how it works, the medicine can also help other allergic conditions, and is currently being studied for use in chronic hives as well as food allergies and may be approved for these conditions in the future.
Angioedema involves rapid swelling of the skin and underlying tissues in response to various causes; it is similar to hives but deeper and is considered a medical emergency because it can close off the airways. Here in the U.S., a new drug has been approved while another is awaiting confirmation for treating this condition: Fyrazyr®
(icatibant) is now available & blocks bradykinin receptors resulting in less swelling while Rhucin®
(a recombinant C1 inhibitor collected from rabbits rather than pooled human plasma) prevents the activation of the blood-borne system that triggers swelling.
Fluzone Intradermal® was licensed by the FDA in the U.S. for use during the 2011-2012 flu season. The intradermal flu vaccine is a shot that is injected into the skin instead of the muscle; it uses a much smaller needle (about 90% smaller!) than the regular flu shot, so it is tolerated better, especially by patients that don’t like injections. It also requires less medicine which means more doses of the vaccine can be available. It provides the same response & protection as the regular flu vaccine.
Sublingual immunotherapy is a way to expose allergic patients to the substances that cause their reactions through an oral route rather than by injection. Not yet approved by the FDA, it ma be available in the near future here in the U.S. Both liquid and tablet forms are currently being used in Europe. Sublingual immunotherapy seems to have a good safety profile although more recent studies suggest that severe allergic reactions (including anaphylaxis) are still possible via this form of administration.
Allergies & asthma are chronic conditions that can require long-term treatment. While it is helpful to have over-the-counter medications readily available that were once prescription, there are patients that still need more powerful therapies. Economic factors determine which medicines will be researched, developed, and manufactured; many good medicines have never made it or are no longer being produced because they were not financially viable. As an allergist, staying up-to-date on what’s coming down the pipeline can be helpful to determine the best treatment for patients.
If you have any questions regarding potential new allergy & asthma treatments, please feel free to contact me.
J. Alex Martinez, M.D.
