An interventional study of Spark Placebo Control 5.1 and Spark Active Study Product 5.1 Usage in Sexual Satisfaction and Sexual Function, sponsored by Radicle Science. Completed at 1 site in United States. Open to female participants aged 21 Years to 105 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2025-08-15.
Sponsored by Radicle Science · Not applicable, Interventional, and Other
A randomized, double-blind, placebo-controlled, direct-to-consumer study assessing the impact of health and wellness products on sexual health and related health outcomes.
This is a randomized, double-blind, placebo-controlled study conducted with adult participants, residing in the United States. Eligible participants will (1) endorse a desire for improved libido (sex drive), sexual satisfaction and/or function, (2) have the opportunity for meaningful improvement (at least 30%) in their primary health outcome, and (3) express acceptance in taking a product and not knowing its formulation until the end of the study. Participants that report a known cardiac dysfunction, liver or kidney disease may be excluded. Participants that report a known contraindication or with well-established, significant safety concerns due to illness will be excluded. Heavy drinkers and those who report they are pregnant, trying to become pregnant, or breastfeeding will be excluded. Participants that report taking medications with a known contraindication or with well-established, significant safety concerns will be excluded. Self-reported data are collected electronically from eligible participants for 7 weeks. Participant reports of health indicators will be collected at baseline, throughout the active period of study product use, and in a final survey. All study assessments will be electronic; there are no in-person visits or assessments for this real-world evidence study.
Radicle Science is the lead sponsor of 64 studies on the registry; 11 are open to participants now.
Counted across the registry records on this site, refreshed daily.
Exclusion Criteria:
Reports a diagnosis of cardiac dysfunction, liver or kidney disease that presents a known contraindication and/or a significant safety risk with any of the study product ingredients.
o NYHA Class III or IV congestive heart failure, atrial fibrillation, uncontrolled arrhythmias, cirrhosis, end-stage liver disease, stage 3b or 4 chronic kidney disease, or kidney failure
Reports taking medications that have a well-established moderate or severe interaction, posing a substantial safety risk with any of the study product ingredients.
o Anticoagulants, antihypertensives, anxiolytics, antidepressants, chemotherapy, immunotherapy, sedative hypnotics, seizure medications, medications that warn against grapefruit consumption, corticosteroids at doses greater than 5 mg per day, diabetic medications, oral anti-infectives (antibiotics, antifungals, antivirals) to treat an acute infection, antipsychotics, MAOIs, or thyroid products
Spark Product 5.1 - control
Dietary Supplement: Spark Placebo Control 5.1
Spark Product 5.1 - active product 1
Dietary Supplement: Spark Active Study Product 5.1 Usage
Participants will use their Radicle Spark Placebo Product 5.1 as directed for a period of 6 weeks.
Participants will use their Radicle Spark Active Study Product 5.1 as directed for a period of 6 weeks.
Change in sexual health
Mean difference in sexual health score as assessed by Patient Reported Outcome Measurement System (PROMIS) Full Profile Sexual Function and Satisfaction Survey (Female) (where lower scores correspond to lower sexual function and satisfaction)
Time frame: 6 weeks
Change in feelings of stress
Mean difference in feelings of stress score as assessed by Perceived Stress Scale 4 (PSS-4) (scale 0-16; where lower scores correspond to less stress)
Time frame: 6 weeks
Change in fatigue
Mean difference in fatigue as assessed by Patient Reported Outcome Measurement System (PROMIS) Fatigue 4A (scale 4-20; where higher scores correspond to more severe fatigue)
Time frame: 6 weeks
Change in mood (emotional distress-depression)
Mean difference in mood score as assessed by PROMIS Emotional Distress- Depression 4A (scale 4-20; where higher scores correspond to more severe emotional distress-depression)
Time frame: 6 weeks
Minimal clinical importance difference (MCID) in sexual health
Likelihood of achieving a MCID in sexual health score as assessed by Patient Reported Outcome Measurement System (PROMIS) Full Profile Sexual Function and Satisfaction Survey (Female) (where lower scores correspond to lower sexual function and satisfaction)
Time frame: 6 weeks
Minimal clinical importance difference (MCID) in feelings of stress
Likelihood of achieving a MCID in feelings of stress score as assessed by Perceived Stress Scale 4 (PSS-4) (scale 0-16; where lower scores correspond to less stress)
Time frame: 6 weeks
Minimal clinical importance difference (MCID) in fatigue
Likelihood of achieving a MCID in feelings of fatigue score as assessed by Patient Reported Outcome Measurement System (PROMIS) Fatigue 4A (scale 4-20; where higher scores correspond to more severe fatigue)
Time frame: 6 weeks
Minimal clinical importance difference (MCID) in mood (emotional distress-depression)
Likelihood of achieving a MCID in mood score as assessed by PROMIS Emotional Distress- Depression 4A (scale 4-20; where higher scores correspond to more severe emotional distress-depression)
Time frame: 6 weeks
Change in saliva concentration of at-home (direct-to-consumer) specimen assay (1)
Mean difference in saliva concentration as assessed by saliva-based IgG (Immunoglobulin) biomarker (Optional; among consented participants only).
Time frame: 6 weeks
Change in saliva concentration of at-home (direct-to-consumer) specimen assay (2)
Mean difference in saliva concentration as assessed by saliva-based cytokines (Interleukin 1 beta, Interleukin 8, Tumor necrosis factor-alpha, and Interleukin 6) biomarker. (Optional; among consented participants only).
Time frame: 6 weeks
Change in saliva concentration of at-home (direct-to-consumer) specimen assay (3)
Mean difference in saliva concentration as assessed by saliva-based dehydroepiandrosterone sulfate (DHEA-S) biomarker. (Optional; among consented participants only).
Time frame: 6 weeks
Change in saliva concentration of at-home (direct-to-consumer) specimen assay (4)
Mean difference in saliva concentration as assessed by saliva-based estradiol biomarker. (Optional; among consented participants only).
Time frame: 6 weeks
Change in saliva concentration of at-home (direct-to-consumer) specimen assay (5)
Mean difference in saliva concentration as assessed by saliva-based progesterone biomarker. (Optional; among consented participants only).
Time frame: 6 weeks
Change in saliva concentration of at-home (direct-to-consumer) specimen assay (6)
Mean difference in saliva concentration as assessed by saliva-based testosterone biomarker. (Optional; among consented participants only).
Time frame: 6 weeks
Change in saliva concentration of at-home (direct-to-consumer) specimen assay (7)
Mean difference in saliva concentration as assessed by saliva-based cortisol biomarker. (Optional; among consented participants only).
Time frame: 6 weeks
Change in saliva concentration of at-home (direct-to-consumer) specimen assay (8)
Mean difference in saliva concentration as assessed by saliva-based melatonin biomarker. (Optional; among consented participants only).
Time frame: 6 weeks
Change in saliva concentration of at-home (direct-to-consumer) specimen assay (9)
Mean difference in saliva concentration as assessed by saliva-based C-Reactive Protein (CRP) biomarker. (Optional; among consented participants only).
Time frame: 6 weeks
Change in blood concentration of at-home (direct-to-consumer) specimen assay (1)
Mean difference in blood concentration as assessed by blood-based cortisol biomarker (1 drop). (Optional; among consented participants only).
Time frame: 6 weeks
Change in blood concentration of at-home (direct-to-consumer) specimen assay (2)
Mean difference in blood concentration as assessed by blood-based homocysteine biomarker (1 drop). (Optional; among consented participants only).
Time frame: 6 weeks
Change in blood concentration of at-home (direct-to-consumer) specimen assay (3)
Mean difference in blood concentration as assessed by blood-based ferritin biomarker (1 drop). (Optional; among consented participants only).
Time frame: 6 weeks
Change in blood concentration of at-home (direct-to-consumer) specimen assay (4)
Mean difference in blood concentration as assessed by blood-based thyroid stimulating hormone (TSH) biomarker (1 drop). (Optional; among consented participants only).
Time frame: 6 weeks
Change in blood concentration of at-home (direct-to-consumer) specimen assay (5)
Mean difference in blood concentration as assessed by blood-based hemoglobin A1C (HbA1c) biomarker (1 drop). (Optional; among consented participants only).
Time frame: 6 weeks
Change in blood concentration of at-home (direct-to-consumer) specimen assay (6)
Mean difference in blood concentration as assessed by blood-based insulin biomarker (1 drop). (Optional; among consented participants only).
Time frame: 6 weeks
Change in blood concentration of at-home (direct-to-consumer) specimen assay (7)
Mean difference in blood concentration as assessed by blood-based vitamin D biomarker (1 drop). (Optional; among consented participants only).
Time frame: 6 weeks
Change in blood concentration of at-home (direct-to-consumer) specimen assay (8)
Mean difference in blood concentration as assessed by blood-based dehydroepiandrosterone sulfate (DHEA-S) biomarker (1 drop). (Optional; among consented participants only).
Time frame: 6 weeks
Change in blood concentration of at-home (direct-to-consumer) specimen assay (9)
Mean difference in blood concentration as assessed by blood-based testosterone biomarker (1 drop) (Optional; among consented participants only).
Time frame: 6 weeks
Change in blood concentration of at-home (direct-to-consumer) specimen assay (10)
Mean difference in blood concentration as assessed by blood-based estradiol biomarker (1 drop). (Optional; among consented participants only).
Time frame: 6 weeks
Change in blood concentration of at-home (direct-to-consumer) specimen assay (11)
Mean difference in blood concentration as assessed by blood-based total cholesterol (high-density lipoproteins (HDL) and low-density lipoproteins (LDL)) biomarker (1 drop). (Optional; among consented participants only).
Time frame: 6 weeks
Change in blood concentration of at-home (direct-to-consumer) specimen assay (12)
Mean difference in blood concentration as assessed by blood-based triglycerides (apolipoprotein A1 (ApoA1) and apolipoprotein B (ApoB)) (1 drop). (Optional; among consented participants only).
Time frame: 6 weeks
Change in stool concentration of at-home (direct-to-consumer) specimen assay
Mean difference in stool concentration as assessed by a stool sample (microbial diversity) (Optional; among consented participants only).
Time frame: 6 weeks
Plan to share: No — Data will not be shared with researchers outside of Radicle Collaborators on this study.
This study is completed, as verified in Aug 2025. You cannot join it, but the record below documents what was studied.
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Orgasm
Radicle Science