Clinical trial NCT05467397: Feasibility of [11C]Acetate-PET in LAM and TSC
Official title: Feasibility Study of [11C]Acetate Positron Emission Tomography (PET) as an Indicator of Early Response to Rapamycin in Lymphangioleiomyomatosis (LAM) Patients
Study type: INTERVENTIONAL
Overall status: RECRUITING
Phase: PHASE1
PHASE2
Conditions: Lymphangioleiomyomatosis
Tuberous Sclerosis Complex
Lead sponsor: Brigham and Women's Hospital
Sponsor class: OTHER
Collaborators: name: Massachusetts General Hospital
First posted: 2022-07-20
Enrollment: 16
Sex: FEMALE
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: NA
Intervention model: SINGLE_GROUP
Primary purpose: DIAGNOSTIC

Brief summary: This study aims to assess \[11C\]acetate positron emission tomography (PET)/computed tomography (CT) as a biomarker for renal angiomyolipomas and pulmonary lymphangioleiomyomatosis (LAM) and an early biomarker of response to rapamycin in LAM patients.

\[11C\]Acetate is a radioactive form of acetate, a nutrient commonly processed in our body's cells to generate fat and energy. Preclinical studies support the hypothesis that TSC tumors enhance lipid synthesis compared to normal tissues, suggesting that quantification of \[11C\]acetate in these tumors by PET/CT may provide a metabolic biomarker of disease.

Participants in the study will undergo 1 or 2 PET/CT scans over 3 to 6 months at the Massachusetts General Hospital (Boston, MA). \[11C\]acetate is administered through an intravenous catheter. This small amount of radioactivity is short-lived and eliminated from the body within a few hours.

Detailed description: Lymphangioleiomyomatosis (LAM) is a rare, multisystem disease of women, consisting of a diffuse proliferation of smooth muscle actin-positive cells (LAM cells), which harbor inactivating mutations in either the TSC1 or TSC2 tumor suppressor gene. These inactivating mutations result in constitutive activation of mammalian/mechanistic TOR (target of rapamycin) complex 1 (mTORC1), which integrates growth factor and nutrient signaling to stimulate cell growth and metabolism. Pulmonary LAM is characterized by associated progressive cystic destruction of the lung parenchyma, recurrent pneumothorax, and chylous pleural effusions. Extrapulmonary proliferative lesions of LAM include renal angiomyolipomas and lymphangiomyomas. LAM can occur as a sporadic disorder where LAM cells harbor somatic inactivating mutations of the TSC1 or TSC2 gene, or in women with Tuberous Sclerosis Complex (TSC).

Rapamycin is an FKBP12-dependent allosteric inhibitor of mTORC1 approved by the FDA for the treatment of LAM and TSC-associated renal angiomyolipomas. Clinical trials of TSC and LAM have shown that 12 month-treatment with rapamycin induces response of renal angiomyolipomas and stabilization of pulmonary function. However, lung function decline and tumor growth resume when treatment is interrupted.

Sensitive and specific biomarkers of response to therapy and/or disease progression, including biomarkers of tumor metabolic activity, would facilitate clinical trials of novel therapeutic agents for LAM and enable optimization of current rapamycin-based regimens.

Our preclinical studies showed that lipogenic pathways can be detected in preclinical animal models of TSC and LAM using PET-based metabolic imaging.

The proposed study aims to quantitatively and non-invasively assess metabolic activity and response to rapamycin in LAM patients using \[11C\]acetate positron emission tomography (PET) imaging.

Eligibility criteria: Inclusion Criteria:

* diagnosis of LAM (or TSC-LAM)
* age 18 or over
* at least one renal angiomyolipoma (at least 1 cm in each diameter) confirmed by CT or MRI
* no prior treatment with rapamycin/rapalogs OR candidate for initiating treatment with rapamycin/rapalogs OR under treatment with rapamycin/rapalogs for minimum 3 months and maximum of 1 year

Exclusion Criteria:

* under treatment with rapamycin or rapalogs for \< 3 months or \> 1 year
* participated in research studies involving radiation exposure (\> 50 mSv/year) in the past 12 months

Primary outcomes:
measure: Quantitative analysis of [11C]acetate uptake in renal angiomyolipoma and pulmonary LAM
timeFrame: 4 months
Secondary outcomes:
measure: Feasibility of [11C]acetate PET as a biomarker of mTORC1 inhibition in LAM/TSC proliferative lesions
timeFrame: 4 months
Other outcomes:
Locations:
city: Boston
country: United States
facility: Brigham and Women's Hospital
state: Massachusetts
Study officials:
affiliation: Brigham and Women's Hospital
name: Carmen P Priolo, MD PhD
role: PRINCIPAL_INVESTIGATOR
References: