Children's prosthetic thoracic device passes FDA postmarket review

The “titanium rib,” a surgically implanted device to treat thoracic insufficiency syndrome, passed through a postmarket review by the US Food and Drug Administration (FDA) Pediatric Advisory Committee in April with flying colors and plaudits from the committee members.

The Vertical Expandable Prosthetic Titanium Rib (VEPTR) is used in children with life-threatening conditions that “may result from intrinsic distortion of the thorax by fused or absent ribs or the consequence of deformity and/or shortening of the thoracic spine,” according to FDA.

It’s the only treatment, the agency notes, that allows the chest cavity to expand vertically, improving lung and heart function and extending life for these terminally ill children.

Robert Campbell Jr., MD, who invented the device in the late 1980s, spoke to the committee, saying he has never seen the same type of VEPTR patient twice. These patients include children with flail chest syndrome; constrictive chest wall syndrome/progressive spinal deformity; hypoplastic thorax syndrome; and progressive congenital, neurogenic, or idiopathic scoliosis without rib fusion. He showed a photo of a child who went from extreme deformity to normal-appearing stance with the device.

Among the complications that arise, he said, are low levels of infections and proximal migration of the devices in about 27% of patients in 3 to 5 years.

The FDA, in its conclusion, said the benefit outweighs the risks and that approval of the device should continue with routine safety monitoring.

Others were more open with praise. In a letter, the Pediatric Orthopaedic Society of North America and the Scoliosis Research Society said that as the “only device specifically approved by FDA for use in select circumstances in preadolescent children, VEPTR has filled a critical need for many children with significant issue.”

With new research, the letter said, “Great progress has been made in [a] short time with regard to better understanding the optimal use of the VEPTR and related devices in various clinical settings.”

Campbell, director of the Center for Thoracic Insufficiency Syndrome, Division of Orthopaedics, Children’s Hospital of Philadelphia, Pennsylvania, and professor of orthopedic surgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, said he felt the future is bright in terms of learning more about these diseases, including things such as their impact on the heart.

Edward Cheng, MD, consultant to the committee, orthopedic surgeon, and Mairs Family Professor at the University of Minnesota Medical School and Cancer Center, Minneapolis, noted that the few alternatives available, including spinal fusion, have not been as successful.

He did say that in some of the studies of the device the children were followed only for a limited time, and he urged that they be followed until their skeletons are mature.

Campbell said his group has been challenged to lower the minimum age for intervention, indicating that the 6-month level had been chosen when the procedures were first undertaken, in part because that gave time to reveal children who would not survive anyway. However, he said, lowering the age is practical now. “It’s just the selection of first cohort to start with.”

Robert Dracker, MD, consultant to the committee and an expert in pediatric hematology at Golisano Children’s Hospital at Strong Memorial, Rochester, New York, said it would be useful to see the outcomes in the day-to-day pediatric needs of these children, such as the incidence of lower respiratory tract infections.

Campbell said anecdotally that the parents are delighted with how much more the children can do. He said his group does have a safety registry and he hopes to have that kind of information in the not-too-distant future.

He also said there is no formal listing of physicians who have had recent training in the procedures and those doctors’ outcomes. However, the physicians doing the procedures are usually the ones who do difficult spinal work, and many institutes have a global reputation for that.

The Pediatric Advisory Committee also agreed with FDA on all the other products reviewed at the meeting: that there were no new issues and that the agency should continue routine monitoring.

Those products include: Activa Dystonia Therapy; Advate (antihemophilic factor [recombinant]); Famvir (famciclovir); Intelence (etravirine); Keppra (levetiracetam); Maxalt and Maxalt MLT (rizatriptan); Natazia (estradiol valerate and estradiol valerate/dienogest); Pertzye (pancrelipase); Perzista (darunavir); Reyataz (atazanavir); Sklice (ivermectin); Tisseel (fibrin sealant); Torisel (temsirolimus); Ultresa (pancrelipase); and Viread (tenofovir disoproxil fumarate).

Presentations from the FDA Pediatric Advisory Committee meeting on April 21, 2014, are available online.

Ms Foxhall is a freelance writer in the Washington, DC, area. She has nothing to disclose in regard to affiliations with or financial interests in any organizations that might have an interest in any part of this article.