A Medical Device Daily

FDA issued a “Dear Doctor” letter earlier this week following reports of patient fatalities in connection with the use of radio frequency (RF) ablation to remove lung tumors.

According to the Dec. 11 letter, such reports have turned up in the medical literature on three occasions since 2004 and current information suggests that “patient selection, subsequent treatment, and technical use of the RF device, including placement and operation, may have contributed to the fatalities.”

According to the 2007 article cited by FDA, which appeared in the journal Vascular and Interventional Radiology, the underlying study examined long-term safety and efficacy in 153 patients who were not candidates for or who refused conventional surgery between 1998 and 2005. This patient group included a total of 189 “primary or metastatic medically inoperable lung cancers,” for which they were treated with percutaneous fluoroscopic CT-guided RF ablation.

The article pegged the overall survival rates for stage I non–small cell lung cancer at one-year increments up to five years as 78% for the first year and trending downward until year five, when the survival rate was 27%.

The authors of the article concluded that RF ablation for lung tumors “appears to be safe and linked with promising long-term survival and local tumor progression outcomes, especially given the patient population treated.”

However, FDA also noted in its statement that RF ablation devices “have not been cleared specifically for lung tumor ablation.” The agency suggested that any doctors who are interested in using RF ablation for lung tumors “should consider enrolling them in an approved clinical study, where training is available.” According to clinical trials.gov, eight such studies are currently recruiting and another five are listed as “active, not yet recruiting.”

FDA recommends gene testing carbamazepine

The road to individualized medicine continues, and FDA continues to play a role in that effort. The agency announced yesterday that product labels for the anti-depressant carbamazepine will henceforth recommend that any patient of Asian ancestry obtain a gene test to check for susceptibility to a rare but often deadly skin reaction.

According to FDA, the prescribing information for carbamazepine “already includes a warning that for all patients ... regardless of ethnicity, rare but severe and sometimes life-threatening skin reactions can occur.” However, those of Asian ancestry apparently are at greater risk for these reactions by an entire order of magnitude.

The list of potential reactions includes two syndromes that occur as a result of toxicity to keratinocytes, which serve to bind the epidermal layers of skin to the dermal layers. Toxic epidermal necrolysis (TEN) is one of these two syndromes and is deadly in as many as 30% to 40% of cases. Another possible reaction is Stevens-Johnson syndrome (SJS), the more severe form of the condition, which may spread to the lining of the bronchial tubes. Many physicians see these as essentially the same pathology and refer to them as SJS/TEN.

The FDA announcement stated that epidemiologists believe that “the risk of these reactions is estimated to be about 1 to 6 per 10,000” in countries with mainly white populations, but see the risk as being about 10 times higher “in some Asian countries.” FDA estimates that about 5% of Americans would have to be tested for this ethnic indication.

Carbamazepine is also used to treat epilepsy, bipolar disorder and neuropathic pain and is sold as Carbatrol, Equetro and Tegretol.

An immune system gene, HLA-B 1502, is thought to be the culprit in this reaction. According to FDA, the gene is “found almost exclusively in people with Asian ancestry.” However, the statement indicated that anyone who has been on the drug for more than “a few months” with no side effects probably has nothing to worry about.

Medicare directors, CMS drop therapist mandate

The influence of specialty societies is a fact of life, especially when they can argue forcefully for the benefit of Medicare beneficiaries. Thus it was that the Centers for Medicare & Medicaid Services (CMS) and local Medicare officials opted to repeal a proposed regulation governing the qualifications of occupational therapists when dealing with powered wheelchairs.

According to a Dec. 11 announcement by the American Occupational Therapy Association (AOTA; Bethesda, Maryland), the two-year effort by AOTA finally convinced CMS “to eliminate a requirement that would have required an additional certification for occupational therapists (OTs) performing wheelchair evaluations for higher-end power devices.” This requirement was part of a local coverage decision on the part of an unspecified entity in 2006, which mandated that OTs and physical therapists acquire certification as assistive technology practitioners (ATPs) in order to be qualified to evaluate patients scheduled to receive Group 2, 3 or 4 wheelchairs. According to the AOTA announcement, this policy “was adopted by each of the medical directors across the country, making it a national policy in effect.”

AOTA’s position is that the certification would not “measure a therapist’s competence in performing evaluations” and that it would “unreasonably restrict a portion of OT practice.” AOTA also made the case that the move “would result in an access problem for Medicare beneficiaries because of the limited number of OTs certified as ATPs.

Christina Metzler, AOTA’s chief public affairs officer said in the statement that the organization “had deep concerns about access for Medicare beneficiaries and an unwarranted restriction on an evaluation that is clearly within the scope of [existing] occupational therapy practice.”

The statement indicated that AOTA met with then-acting CMS co-administrator Herb Kuhn last year to discuss the matter, which “was followed by a formal request for reconsideration of the LCD, including a telephone conference call with regional Medicare medical directors.” This latter group announced on Dec. 3 that it would drop the requirement.

As a result, any patients for whom a wheelchair is indicated “must have a specialty evaluation performed by a licensed/certified medical professional such as an OT or physical therapist, or by a physician who has specific training and experience in rehabilitation wheelchair evaluations,” which is the current requirement.