Which patients with acromegaly are treated with pegvisomant? An overview of methodology and baseline data in ACROSTUDY

Abstract

Context: Pegvisomant (Somavert, Pfizer Inc.) is the first and only available GH receptor antagonist. ACROSTUDY is an international surveillance study that offers inclusion in a web-based registry to all patients with acromegaly treated with pegvisomant; it aims at monitoring long-term safety and efficacy of this compound. Results: Of all patients, 80% were reported to have had surgery and 33% to have received radiation therapy. Of the 792 patients, 14% had received no prior medical treatment before pegvisomant start, 65.9% had received somatostatin analogues and 18.6% dopamine agonists. Interestingly, 66.7% had received only pegvisomant at study start, while it was taken in association with dopamine agonists in 5.7%, with somatostatin analogues in 23.4% and with both types of agents in 3.8%. Mean IGF1 at baseline was 522 ng/ml. Conclusion: Analysis of the baseline features of these patients treated with pegvisomant and reported in the ACROSTUDY database underscores the severity of the disease in this subset of the population of patients with acromegaly previously unresponsive to several medical, surgical or radiation treatment approaches.

Prediction of therapy response in acromegalic patients under pegvisomant therapy within the German ACROSTUDY cohort

“…And in a study by Parkinson et al [21] in 118 acromegalic patients, gender, body weight, previous radiotherapy, and baseline GH/IGF-1 influenced the pegvisomant dosage that was needed to reach biochemical control. Additionally, the role of the diabetes status in the pegvisomant therapy scheme has been emphasized as patients with acromegaly and type 2 diabetes mellitus require higher pegvisomant dosages to achieve IGF-1 normalisation than acromegalic patients without diabetes mellitus [22][23][24][25].…”

Pegvisomant Treatment in Acromegaly

“…In the literature, different efficacies of PEG-V are reported ranging from around 60 to over 90% [10,11,12,13,14,15]. The studies that reported lower efficacy levels are all observational studies [11,12,14,15,16].…”

“…The studies that reported lower efficacy levels are all observational studies [11,12,14,15,16]. These observational studies were not designed to assess efficacy but were designed to assess additional medical information, such as rare side effects and other safety aspects.…”

Profile of pegvisomant in the management of acromegaly: an evidence based review of its place in therapy

“…Several interim analysis from ACROSTUDY have been published. [25][26][27][28] The last publication 26 included 1,288 patients. After 5 years of PEG treatment, 63.2% of cases had normal IGF-I levels.…”

“…2 Combination therapy, usually with daily PEG, 26 is increasingly being used in recent years. While in the GPOS no cases of combined treatment were described, 30 in the ACROSTUDY 2009, 27 22.4% of the patients were receiving combination therapy with PEG plus SSA and 3.8% PEG plus SSA plus CAB. In ACROSTUDY 2012, 26 36.6% of subjects were on combination therapy.…”