Data Shows Zonegran(R) (Zonisamide) Is Well-Tolerated By Elderly Patients With Partial Epilepsy

Date: Jul-17-2013Pooled-analysis shows zonisamide as an effective partial epilepsy treatment for the elderly, as well as adults.

Results from a pooled-analysis, published today in Acta Neurologica Scandinavica, show
Zonegran(R) (zonisamide) is a well-tolerated treatment for partial seizures with or without secondary generalisation in the elderly population (65 years and above), when used as a monotherapy or adjunctive (add-on) therapy.

The safety results observed in the elderly patients (n=95) were similar to that seen in adults (n=1389), however, the incidence of treatment related and serious adverse events reported was lower, respectively 56% vs. 73%, 13% vs. 17%. Most treatment emergent adverse effects (TEAEs) were of mild-to-moderate intensity. The only serious or severe TEAEs reported by greater than or equal to2% elderly patients were 'convulsions' ([4%]). A decrease in weight of >10% in 11% of monotherapy-treated elderly patients was also noted. Zonisamide demonstrated a favourable safety/tolerability profile in elderly patients. No new or unexpected safety findings were identified' [1] A pooled analysis of safety data on the 95 elderly subjects has shown a relatively higher reporting frequency of peripheral oedema and pruritus compared to the adult population. Review of post-marketing data suggests that patients aged 65 years or older report a higher frequency than the general population of the following events: Stevens-Johnson syndrome (SJS) and Drug Induced
Hypersensitivity syndrome (DIHS). However, this analysis could not assess these effects due to the small patient numbers.

Compared with the younger adult population, epilepsy in elderly patients differs in terms of aetiology, clinical presentation and prognosis.[2] The management of epilepsy in the elderly is complicated and challenging, particularly since levels of comorbidity and the need for associated medication are high.[3] Mortality among elderly people with epilepsy is particularly high, with 30 per cent of acute seizures resulting in status epilepticus, a life-threatening state where a seizure lasts 30 minutes or longer, or patients experience a cluster of shorter seizures for 30 minutes or more, with little or no recovery in between, carrying a 40 per cent risk of mortality.[4],[5]

A quarter of newly diagnosed cases of epilepsy are in the elderly population.[6] In Europe, it's estimated 600,000 people aged 65 years and over have epilepsy, equivalent to 7 in 1,000. There are approximately 85,000 new cases being diagnosed each year,[7] and nearly one third of European citizens will be aged 65 or over by 2060.[8]

"The elderly analysis provides healthcare professionals and patients with the confidence and knowledge that zonisamide is a well-tolerated treatment approach for managing elderly people's epilepsy, which is also supported by its already strong heritage in the treatment of the condition," commented Eugen Trinka, Professor of Neurology, Paracelsus Medical University, Salzburg, Austria.

An effective monotherapy and add-on treatment, once-daily zonisamide is a second generation anti-epileptic drug (AED) with multiple mechanisms of action and a chemical structure which is unrelated to any other AEDs.[9] In the recent ILAE evidence review, Zonegran was classed as one of only 4 AEDs with level A efficacy/effectiveness evidence as initial monotherapy for adults with partial onset seizures.[10]

"Epilepsy affects a significant number of elderly people and there has been surprisingly little research into the condition in this patient population. These encouraging new data enhance our knowledge of Zonegran and show that it is a well-tolerated once-daily monotherapy or adjunctive treatment in wider patient groups, such as the elderly," commented Luigi Giorgi, Eisai Europe.

The continued development of zonisamide underscores Eisai's human health care mission,
the company's commitment to innovative solutions in disease prevention, cure and care for
the health and well being of people worldwide. Eisai is committed to the therapeutic area of epilepsy and addressing the unmet medical needs of patients with epilepsy and their families. Eisai is proud to currently market more epilepsy products in EMEA than any other company.

About Zonegran (zonisamide)

Zonisamide is licensed in Europe as once-daily monotherapy in the treatment of partial seizures, with or without secondary generalisation, in adults with newly diagnosed epilepsy. In addition, zonisamide is also indicated as a once-daily adjunctive therapy in the treatment of partial seizures (with or without generalisation) in adults with epilepsy. It has a broad spectrum of anti-epileptic modes of action and has no appreciable effects on steady-state plasma concentrations of other AEDs, such as phenytoin, carbamazepine and valproate.[9]

Zonisamide is available in 25mg, 50mg, and 100mg capsule strengths. In the first two weeks, the recommended daily dose for monotherapy use is 100mg/day. In the third and fourth weeks the dose may be increased to 200 mg daily and then increased to 300mg daily after the next two weeks. The recommended initial daily dose for adjunctive use is 50mg in two divided doses. After one week the dose may be increased to 100 mg daily and thereafter the dose may be increased at weekly intervals, in increments of up to 100 mg.[9]

About Epilepsy

Epilepsy is one of the most common neurological conditions in the world, affecting approximately eight in 1,000 people in Europe, and an estimated 50 million people worldwide.[11],[12]Epilepsy is a chronic disorder of the brain that affects people of all ages. It is characterised by abnormal discharges of neuronal activity causing seizures. Seizures can vary in severity, from brief lapses of attention or jerking of muscles, to severe and prolonged convulsions. Depending on the seizure type, seizures may be limited to one part of the body, or may involve the whole body. Seizures can also vary in frequency from less than one per year, to several per day. Epilepsy has many possible
causes but often the cause is unknown.

Zonegran in the elderly[1]

A study assessing the tolerability and safety of zonisamide in elderly patients with partial epilepsy which used a pooled analysis of data from 95 elderly patients over 65 years and compared to pooled data from 1389 adults (18-65 years).[13] The assessments included treatment-emergent AEs, clinical laboratory tests and weight. Zonisamide was found to be well-tolerated by elderly patients when compared to adults and no new or unexpected safety findings were identified in the study.

Overall incidence of treatment-emergent adverse events (TEAEs) was similar in elderly versus adult patients (78/95 [82%] vs. 1165/1389 [84%]). Incidence was lower in elderly versus adult patients for severe TEAEs (11/95 [12%] vs. 299/1463 [20%]) and TEAEs leading to withdrawal (17/95 [18%] vs. 324/1463 [22%]). Most TEAEs were of mild-to-moderate intensity. TEAEs reported by greater than or equal to5% of patients in either cohort and more frequently by elderly versus adult patients were fatigue (11/95 [12%] vs. 135/1389 [10%]), nasopharyngitis (8/95 [8%] vs. 100/1389 [7%]), constipation (7/95 [7%] vs. 67/1389 [5%]), peripheral oedema (4/95 [4%] vs. 18/1389 [1%]), pruritus (6/95 [6%] vs. 29/1389 [2%]), and oropharyngeal pain (2/95 [2%] vs. 3/1389 [0.2%]).

The only serious or severe TEAEs reported by greater than or equal to2% elderly patients were 'convulsions' (4/95 [4%]) Three elderly patients died but only one death was considered treatment-related (circulatory collapse following pancreatitis). TEAEs leading to discontinuation of greater than or equal to2% of elderly patients were dizziness (4/95 [4%]), headache (2/95 [2%]), somnolence (2/95 [2%]) and confusional state (2/95 [2%]). For elderly patients, there were minimal clinically significant changes in clinical laboratory parameters, no reports of respiratory alkalosis or metabolic acidosis, and no significant weight changes.

A review of post-marketing data suggested that patients aged 65 years or older report a higher frequency than the general population of the following events: Stevens-Johnson syndrome (SJS) and Drug Induced Hypersensitivity syndrome (DIHS). However this analysis could not assess the effects of zonisamide on the incidence of certain adverse events of special interest, such as Stevens Johnson syndrome, pneumonia and bone disorders, which occur at frequencies too low to be investigated in such small patient numbers.[9]

Courtesy: Medical News Today Note: Any medical information available in this news section is not intended as a substitute for informed medical advice and you should not take any action before consulting with a health care professional.