How was Macrilen studied?
Macrilen was studied in adults in a head-to-head trial vs the gold standard (insulin tolerance test [ITT]), n=1401,2*†
Positive agreement was the proportion of subjects who tested positive for Adult Growth Hormone Deficiency (AGHD) with both the ITT and Macrilen tests.
Negative agreement was the proportion of subjects who tested negative for AGHD with both the ITT and Macrilen tests.
The prespecified cut-point for a diagnosis of AGHD with Macrilen was <2.8 ng/mL for the 4 blood draws.1
Enrolled safety and modified intention-to-treat (mITT) populations: Of 166 enrolled subjects, 157 subjects received at least 1 dose of the study drug and formed the safety population. Of the 157 subjects, 17 did not fulfill the mITT criterion (randomized subjects in whom both tests of the crossover were evaluable).2
Studied in adult subjects with different pretest probabilities of GH deficiency (GHD) and in healthy control subjects.1
Who was tested for AGHD?1
Macrilen agreement with the ITT
Overall, the diagnostic accuracy of Macrilen was comparable to the ITT1
In patients with an intermediate likelihood of AGHD, agreement between Macrilen and the ITT was1
- 67% positive
- 86% negative
- 70% overall
In patients with a low likelihood of AGHD, agreement between Macrilen and the ITT was1
- 33% positive
- 94% negative
- 85% overall
In healthy patients, agreement between Macrilen and the ITT was1
- 0% positive
- 96% negative
- 92% overall
- More than 99% (153/154) of Macrilen tests performed successfully on the first attempt1‡
- 83% (130/157) of the ITTs performed successfully on the first attempt1
– 17% failed to achieve severe hypoglycemia
- Reproducibility was observed in 91.2% of a European subset of 34 subjects who underwent 2 Macrilen tests1
- In subjects with a high likelihood of AGHD and in the healthy adult control group, Macrilen had a sensitivity of 87% and a specificity of 96%2§
‡1 test failed due to a technical error.1
§For exploratory analyses, sensitivity and specificity for both GH stimulation tests were estimated, assuming all high probability (Group A) AGHD subjects as “true” AGHD subjects and all healthy matching subjects (Group D) as “true” AGHD-negative subjects. For full information on all study groups, see full study design above.3
Macrilen was well tolerated in a clinical trial1,2
Common adverse events (AEs) in <5% of subjects1
No AEs led to a failure to complete the Macrilen test.1
There are no contraindications with Macrilen.1
References: 1. Macrilen [prescribing information]. Trevose, PA: Strongbridge U.S. Inc.; 2018. 2. Data on file. Strongbridge U.S. Inc. 3. Garcia JM, Biller BMK, Korbonits M, et al. Macimorelin as a diagnostic test for adult growth hormone deficiency [published online ahead of print May 31, 2018]. J Clin Endocrinol Metab. doi:10.1210/jc.2018-00665.
Macrilen is indicated for the diagnosis of adult growth hormone deficiency (AGHD).
Limitations of Use
The safety and diagnostic performance of Macrilen have not been established for subjects with a body mass index (BMI) > 40 kg/m2.
Important Safety Information
Warnings and Precautions
Macrilen causes an increase of about 11 msec in the corrected QT (QTc) interval. QT prolongation can lead to development of torsade de pointes-type ventricular tachycardia with the risk increasing as the degree of prolongation increases. The concomitant use of Macrilen with drugs that are known to prolong the QT interval should be avoided.
Potential for False Positive Test Results with Use of Strong CYP3A4 Inducers
Concomitant use of strong CYP3A4 inducers with Macrilen can decrease macimorelin plasma levels significantly and thereby lead to a false positive result. Strong CYP3A4 inducers should be discontinued and enough time should be given to allow washout of CYP3A4 inducers prior to test administration.
Potential for False Negative Test Results in Recent Onset Hypothalamic Disease
Adult growth hormone (GH) deficiency caused by a hypothalamic lesion may not be detected early in the disease process. Macimorelin acts downstream from the hypothalamus and macimorelin stimulated release of stored GH reserves from the anterior pituitary could produce a false negative result early when the lesion involves the hypothalamus. Repeat testing may be warranted in this situation.
The most common adverse reactions were dysgeusia, dizziness, headache, fatigue, nausea, hunger, diarrhea, upper respiratory tract infection, feeling hot, hyperhidrosis, nasopharyngitis, and sinus bradycardia
Please see Full Prescribing Information.
900 Northbrook Drive, Suite 200
Trevose, PA 19053
Phone: +1 610-254-9200