(Connective Issues, Spring 2007)

The losartan versus atenolol clinical trial has begun. The coordinators at each site are ready to receive calls and e-mails from anyone interested in participating.

The trial, which studies losartan, a commonly prescribed blood pressure medication, and atenolol, a beta-blocker that is currently the “gold standard” for treating people with Marfan syndrome, requires 600 participants. The faster we enroll the 600 participants, the sooner we can have meaningful results.

Study participants can be assured they will receive the utmost care and oversight. The Data Safety and Monitoring Board will keep close track of all the data collected from the study. If the Board sees clear evidence that one medication is better than the other, the study will be stopped and the results will be announced.

The clinical trial is the only way we can obtain answers to questions vital to the management of Marfan syndrome. It is the only way accepted by the medical community to find out if losartan is effective in people and, if effective, the way it can become an accepted standard of care for Marfan syndrome. Having an established and documented standard of care will make it much easier to get medical insurance to cover the cost of losartan therapy. Here are some of the questions the trial can help answer:

• Does losartan effect growth of the aorta in people who have Marfan syndrome similar to the way it effects growth of the aorta in mice with Marfan syndrome?
• Does losartan effect growth of the aorta in all people who have Marfan syndrome or in just some people?
• Does losartan help some people more than others? If so, which people?
• Does the age when a person starts taking losartan make a difference?
• Does the size of the aorta when a person starts losartan make a difference?
• How much losartan should a person take (what is the best dosage) to have a desired effect?
• Even though losartan is FDA approved and thought to be safe, does losartan have unwanted effects in people who have Marfan syndrome that are not seen in the general population?
• Is losartan clearly better than atenolol for managing Marfan syndrome?

Even though there are reports that losartan has helped a few severely affected children, it is not known if it will help most people who have Marfan syndrome. There are very real reasons not to take losartan outside of the trial. These reasons include:

• The amount of losartan (the dose) may be incorrect and/or not enough to make a difference. Any protection offered by your beta blocker may be lost and not replaced by an incorrect amount of losartan.
• The trial has plans in place to quickly recognize and manage any adverse reactions. Your doctor is unlikely to be this well-prepared.
• The trial very carefully describes who is eligible to participate based on their medical status. There are medical reasons why not everyone is eligible for the trial. Your doctor is unlikely to be aware of all of the medical issues the trial has taken into account and may not understand how losartan may help manage Marfan syndrome.
• Losartan is not a substitute for aortic surgery in people whose aorta has reached the size where surgery is recommended. It is dangerous to think that taking losartan will prevent a dissection in a significantly dilated aorta.
• The effects of losartan in people who already have had an aortic dissection repaired, or who have a chronic dissection, are not known. It is possible that taking losartan can make the dissection worse or unstable.

In summary, the NMF urges anyone who thinks they are eligible to participate in the trial to contact a trial site and find out more about the trial. Only through the trial will we:

• Get the answers we need to really know if losartan should become the drug of choice in the management of Marfan syndrome.
• Find out if losartan is safe for people who have Marfan syndrome
• Decide if losartan is the standard of care that doctors will accept and insurance companies must cover.