Novel Therapy Eases Cushing's Symptoms in Pivotal Trial

[~MaryO~]

by Kristen Monaco, Staff Writer, MedPage Today

LOS ANGELES -- An investigational therapy improved quality of life and reduced disease symptoms for patients with endogenous Cushing's syndrome, according to new findings from the phase III SONICS study.

Patients taking oral levoketoconazole twice daily had significant reductions in mean scores for acne (-1.8), peripheral edema (-0.4), and hirsutism (-2.6), all secondary endpoints of the pivotal trial (P<0.03 for all), reported Maria Fleseriu, MD, of Oregon Health and Science University in Portland.

"We're looking forward to see the results of further studies and to add this therapy to the landscape of Cushing's," Fleseriu said here during a presentation of the findings at AACE 2019, the annual meeting of the American Association of Clinical Endocrinologists. "We have a newer medication and still we cannot make a dent in the outcomes of Cushing's, especially for patient-reported outcomes."

Free testosterone levels significantly decreased in women taking levoketoconazole (a ketoconazole stereoisomer and potent steroidogenesis inhibitor), from an average of 0.32 ng/dL down to 0.12 ng/dL (0.011 to 0.004 nmol/L, P<0.0001). Men had a non-significant increase: 5.1 ng/dL up to 5.8 ng/dL (0.177 to 0.202 nmol/L).

There were no significant changes from baseline to the end of maintenance for other secondary endpoints in the analysis: moon facies, facial plethora, striae, bruising, supraclavicular fat, irregular menstruation, and dysmenorrhea. However, significant improvements after 6 months of therapy were seen in patient-reported quality of life compared with baseline (mean 10.6 change on the Cushing QOL questionnaire) as well as a significant reduction in depressive symptoms (mean -4.3 change on the Beck Depression Inventory II).

The open-label, multicenter SONICS (Study of Levoketoconazole in Cushing's Syndrome) trial included 94 adult men and women with a confirmed diagnosis of Cushing's syndrome and elevated 24-hour mean urinary free cortisol (mUFC) levels at least 1.5 times the upper limit of normal.

In the dose-titration phase of the study (weeks 2 to 21), patients were titrated up to a max dose of 600 mg levoketoconazole twice daily until mUFC normalization. A 6-month maintenance phase followed with no dose increases, but decreases were allowed if adverse events emerged. An additional 6-month extended evaluation phase followed thereafter.

The study met it's previously reported primary endpoint, with 30% of patients achieving normalized mUFC levels after 6 months of maintenance therapy without a dose increase (95% CI 21%-40%, P=0.0154).

Levoketoconazole was well tolerated, with only 12.8% of patients discontinuing treatment due to adverse events. The most commonly reported adverse events were nausea (31.9%), headache (27.7%), peripheral edema (19.1%), hypertension (17%), and fatigue (16%), some of which were expected due to steroid withdrawal, Fleseriu said.

Serious adverse events were reported in 14 patients, including prolonged QTc interval in two patients, elevated liver function in one patient, and adrenal insufficiency in another, events similar to those seen with ketoconazole (Nizoral) therapy.

Fleseriu explained that drug-drug interaction is a problem in Cushing's, as all of the available medications prolong QT interval.

She noted that in SONICS, QT prolongation with levoketoconazole was observed in few patients. It's still a "concern," said Fleseriu, especially for patients on other drugs that prolong QT.

Although not yet approved, levoketoconazole has received orphan drug designation from the FDA and the European Medicines Agency for endogenous Cushing's syndrome. The tentative brand name is Recorlev.

 

The study was supported by Strongbridge Biopharma.

Fleseriu reported relationships with Strongbridge, Millendo Therapeutics, and Novartis. Co-authors also disclosed relevant relationships with industry.

• Primary Source

  American Association of Clinical Endocrinologists

  Source Reference: Fleseriu M, et al "Levoketoconazole in the treatment of endogenous Cushing's syndrome: Improvements in clinical signs and symptoms, patient-reported outcomes, and associated biochemical markers in the phase 3 SONICS study" AACE 2019; Poster 369.

From https://www.medpagetoday.com/meetingcoverage/aace/79465