Paid Clinical Trials in California

California has 6,480 paid clinical trials enrolling now across cities including Los Angeles, San Francisco and San Diego. Search by condition, age, or phase to find compensated research studies accepting participants near you.

Research sites in California include Stanford Medicine, UCLA Health and UCSF, running studies across oncology, cardiology, neurology, and more. The most actively recruiting conditions are Breast Cancer, Prostate Cancer, Obesity, Colorectal Cancer — browse the full list or use the filters to match your diagnosis. Both patients and healthy volunteers may qualify. Most studies offer compensation for time and travel.

Recruiting trial data synced daily from ClinicalTrials.gov. Last sync: .

Filter results
Filter results

6,480 clinical trials

↓ Download CSV

Adaptive Cell Phone Support (ACPS)

for Medication Adherence
1 location in Los Angeles
Sponsor: Children's Hospital Los Angeles
Sex: All·Age: 15 - 20
Code: NCT07064824·Not Yet Recruiting

Hearing Loss and Brain Health Study

for Hearing Loss, Adult-Onset
1 location in Los Angeles
Sponsor: University of Southern California
Sex: All·Age: 50+
Code: NCT07288463·Not Yet Recruiting

Cochlear Implantation and Social Outcomes

for Hearing Loss, Bilateral Sensorineural
1 location in Los Angeles
Sponsor: University of Southern California
Sex: All·Age: 60+·Accepts healthy volunteers
Code: NCT07584837·Not Yet Recruiting

Group PACBT for Depression

for Depression - Major Depressive Disorder
1 location in Los Angeles
Sponsor: University of California, Los Angeles
Sex: All·Age: 21 - 60
Code: NCT07566104·Phase 2·Not Yet Recruiting

Improv Music Therapy for Older Adults

for Alzheimer's Disease (AD)
1 location in San Francisco
Sponsor: University of California, San Francisco
Sex: All·Age: 60+·Accepts healthy volunteers
Code: NCT07419022·Not Yet Recruiting

About research studies in California

California has approximately 6,480 recruiting research studies across a wide range of therapeutic areas. California hosts a dense network of world-class research institutions, including UC San Diego Health, Stanford Medicine, UCLA Health, UCSF, City of Hope, and Scripps Research. The state's thriving biotech corridor and diverse patient population make it a national hub for both early-phase and late-phase clinical research.

Common conditions studied in California

  • Breast Cancer (101 active studies). Breast cancer trials evaluate new hormone therapies, targeted drugs, and immunotherapy combinations aimed at improving survival and reducing recurrence.
  • Prostate Cancer (79 active studies). Prostate cancer studies test next-generation hormone therapies, PARP inhibitors, and radioligand treatments for both localized and advanced disease.
  • Obesity (71 active studies). Obesity trials evaluate GLP-1 and GIP receptor agonists, novel metabolic drugs, and combined lifestyle interventions for sustainable weight loss.
  • Colorectal Cancer (66 active studies). Colorectal cancer trials explore novel chemotherapy combinations, targeted agents, and immunotherapy for microsatellite-instability-high tumors.
  • Cancer (59 active studies). Recruiting Cancer studies evaluate investigational treatments, diagnostics, and supportive care approaches to improve patient outcomes.
  • Heart Failure (58 active studies). Heart failure trials explore SGLT-2 inhibitors, novel myosin modulators, and device-based therapies for both reduced and preserved ejection fraction.

Leading research sponsors in California

  • Stanford University
  • University of California, San Francisco
  • University of California, Los Angeles
  • City of Hope Medical Center
  • University of California, San Diego

Local regulations and guidelines

Clinical trials in California are governed by U.S. Food and Drug Administration (FDA) regulations, Office for Human Research Protections (OHRP) standards, and federal HIPAA privacy rules. Every study is reviewed by an Institutional Review Board (IRB) to protect participant safety and ensure informed consent. In addition, California-specific protections such as the California Consumer Privacy Act (CCPA) and the Confidentiality of Medical Information Act (CMIA) impose stringent data-privacy requirements on research involving California residents.

Compensation & what to expect

How payment typically works
Compensation is most often provided through reloadable electronic study cards or direct deposit, paid out per completed visit rather than as a lump sum. Amounts vary by the time required, the number of visits, and the study's complexity — overnight stays and inpatient pharmacology studies generally pay more than short outpatient surveys. The exact amount is disclosed in writing during informed consent before any visit.
Healthy volunteers
Healthy participants aged 18 and older can earn compensation by joining vaccine, pharmacology, and biomarker studies in California. These trials check how a new drug or vaccine behaves in healthy bodies before later-phase testing. Many sites maintain a healthy-volunteer registry so you hear about new opportunities first.
What's included beyond payment
Most trials cover study-related medical care at no cost — physical exams, lab work, imaging, the investigational treatment itself, and follow-up visits with the research team. Insurance is not required to participate. Free check-ups and access to specialists are common reasons participants return for additional studies.
Travel and time
Many sponsors reimburse travel, parking, mileage, and lost wages for visit days. Long-running studies and trials that require frequent visits often raise stipends accordingly. Ask the study coordinator for the visit schedule and reimbursement policy before you commit.
Asking about compensation
Compensation is set per protocol and per site, so figures are not published in trial registries. The fastest way to confirm payment for a specific study is to contact the recruiting site listed on the study record. Coordinators are accustomed to this question and will quote the per-visit and total amounts up front.

How to find a clinical trial in California

Hipa.ai aggregates every recruiting study in California from ClinicalTrials.gov and refreshes the list daily. Use the filters above to narrow by condition, facility, age, phase, or healthy-volunteer eligibility, then click any study title to view full details — eligibility criteria, intervention, location, and sponsor contact information. To enroll, reach out to the central study contact listed on the study detail page; the research coordinator will walk you through the screening process.

Frequently asked questions

How many paid clinical trials are currently recruiting in California?

There are approximately 6,480 recruiting clinical trials in California listed on ClinicalTrials.gov. The number changes weekly as new studies open and others close enrollment.

Do clinical trials in California pay participants?

Most recruiting trials in California compensate participants for their time, travel, and study visits. Compensation varies by sponsor, study phase, and visit requirements — the exact amount is disclosed by the study team during the informed consent process.

Who can participate in a clinical trial in California?

Eligibility depends on the specific study. Each trial defines its own inclusion criteria (age, diagnosis, medical history, prior treatments) and exclusion criteria. Both patients with specific conditions and healthy volunteers can qualify, depending on the study design.

What conditions are most commonly studied in California?

The most common conditions under active study in California include Breast Cancer (101), Prostate Cancer (79), Obesity (71), Colorectal Cancer (66), among many others. Browse the list above to explore every recruiting trial.

Are there clinical trials for healthy volunteers in California?

Yes. Healthy-volunteer studies — often early-phase pharmacology or vaccine trials — recruit in California on an ongoing basis. Use the "Healthy volunteers only" filter above to view trials that accept participants without the study's target condition.

How do I enroll in a clinical trial in California?

Click any study title above to see the full study record, including eligibility criteria, visit schedule, and the study team's contact information. Reach out to the central contact or recruiting site directly — they will guide you through screening and informed consent.

Browse more clinical trials

All cities in California

Los Angeles, CA(2,058)San Francisco, CA(1,435)San Diego, CA(809)Palo Alto, CA(681)Sacramento, CA(617)La Jolla, CA(579)Duarte, CA(574)Orange, CA(542)Stanford, CA(443)Irvine, CA(387)Newport Beach, CA(216)Santa Monica, CA(215)Long Beach, CA(210)Walnut Creek, CA(194)Oakland, CA(189)Torrance, CA(188)Loma Linda, CA(174)Beverly Hills, CA(169)Anaheim, CA(126)Santa Rosa, CA(122)Fresno, CA(117)Pasadena, CA(112)Glendale, CA(108)Fountain Valley, CA(103)Redwood City, CA(103)Fullerton, CA(100)Los Alamitos, CA(97)Riverside, CA(89)San Jose, CA(89)Fremont, CA(86)Huntington Beach, CA(86)Lancaster, CA(84)Roseville, CA(82)Santa Barbara, CA(76)Upland, CA(74)Berkeley, CA(73)Vallejo, CA(73)Bakersfield, CA(72)Modesto, CA(71)Burbank, CA(66)Santa Ana, CA(64)Northridge, CA(63)Thousand Oaks, CA(61)Garden Grove, CA(57)San Luis Obispo, CA(56)Santa Maria, CA(55)Stockton, CA(54)Arroyo Grande, CA(53)Dublin, CA(53)Encino, CA(53)Chula Vista, CA(52)Oceanside, CA(52)Santa Clara, CA(52)San Leandro, CA(51)Bellflower, CA(49)Davis, CA(49)Rocklin, CA(47)Carmichael, CA(46)San Rafael, CA(46)Elk Grove, CA(45)Pomona, CA(45)Downey, CA(44)La Mesa, CA(44)Mountain View, CA(42)Woodland, CA(42)South San Francisco, CA(41)Whittier, CA(40)San Mateo, CA(39)Sunnyvale, CA(39)Napa, CA(38)Oxnard, CA(38)Rancho Mirage, CA(38)Encinitas, CA(37)Madera, CA(37)West Hills, CA(37)Canoga Park, CA(36)Redlands, CA(34)Tarzana, CA(34)South Pasadena, CA(33)Ventura, CA(33)Fontana, CA(32)Escondido, CA(31)Merced, CA(31)Palm Springs, CA(30)Sherman Oaks, CA(30)Cerritos, CA(29)Covina, CA(29)Panorama City, CA(29)Vista, CA(29)West Los Angeles, CA(29)Murrieta, CA(28)Ontario, CA(28)Auburn, CA(27)Culver City, CA(27)San Marcos, CA(27)Coronado, CA(26)Laguna Hills, CA(26)Martinez, CA(26)Poway, CA(26)Santa Cruz, CA(26)West Hollywood, CA(26)Carlsbad, CA(25)Inglewood, CA(25)San Bernardino, CA(25)Woodland Hills, CA(25)Corona, CA(24)Harbor City, CA(24)Richmond, CA(23)Tustin, CA(23)Vacaville, CA(23)Van Nuys, CA(23)Baldwin Park, CA(22)Cameron Park, CA(22)Chino, CA(22)Clovis, CA(22)Concord, CA(22)Huntington Park, CA(22)Montclair, CA(22)Antioch, CA(21)Costa Mesa, CA(21)Emeryville, CA(21)Lemon Grove, CA(21)Valencia, CA(21)Castro Valley, CA(20)San Dimas, CA(20)Burlingame, CA(19)Rancho Cordova, CA(19)Redding, CA(19)Sylmar, CA(19)Greenbrae, CA(18)Lake Forest, CA(18)Novato, CA(18)Rohnert Park, CA(18)La Palma, CA(17)Pleasanton, CA(17)St. Helena, CA(17)Arcadia, CA(16)Marysville, CA(16)Santa Clarita, CA(16)Chico, CA(15)Imperial, CA(15)Colton, CA(14)Granada Hills, CA(14)Truckee, CA(14)West Covina, CA(14)Rialto, CA(13)Salinas, CA(13)Victorville, CA(13)Mission Viejo, CA(12)Rolling Hills Estates, CA(12)Spring Valley, CA(12)Temecula, CA(12)Lakewood, CA(11)Apple Valley, CA(10)Folsom, CA(10)Mission Hills, CA(10)Rancho Cucamonga, CA(10)Alhambra, CA(9)Aliso Viejo, CA(9)Buena Park, CA(9)Cypress, CA(9)Pico Rivera, CA(9)Del Mar, CA(8)El Centro, CA(8)Gardena, CA(8)Lafayette, CA(8)Lomita, CA(8)Monterey, CA(8)North Hollywood, CA(8)Petaluma, CA(8)Campbell, CA(7)Lincoln, CA(7)Mather, CA(7)Tujunga, CA(7)Westlake Village, CA(7)El Segundo, CA(6)La Habra, CA(6)Laguna Niguel, CA(6)Moreno Valley, CA(6)Palmdale, CA(6)Westwood, Los Angeles, CA(6)El Cajon, CA(5)Lynwood, CA(5)Manhattan Beach, CA(5)Monrovia, CA(5)San Carlos, CA(5)Solvang, CA(5)Toluca Lake, CA(5)Valley Village, CA(5)Westminster, CA(5)Larkspur, CA(4)Marina del Rey, CA(4)Menifee, CA(4)Montebello, CA(4)Norco, CA(4)Rancho Santa Margarita, CA(4)Redondo Beach, CA(4)San Juan Capistrano, CA(4)San Ramon, CA(4)South Gate, CA(4)Yorba Linda, CA(4)Azusa, CA(3)Brisbane, CA(3)Camarillo, CA(3)Castroville, CA(3)Cupertino, CA(3)Glendora, CA(3)Lodi, CA(3)Los Altos, CA(3)Los Gatos, CA(3)Monterey Park, CA(3)Newhall, CA(3)North Hills, CA(3)Palm Desert, CA(3)Paramount, CA(3)Simi Valley, CA(3)Bishop, CA(2)Brea, CA(2)California City, CA(2)Camp Pendleton, CA(2)Daly City, CA(2)El Cerrito, CA(2)Fair Oaks, CA(2)Hawthorne, CA(2)Hemet, CA(2)Indian Wells, CA(2)Laguna Woods, CA(2)Lakeport, CA(2)Menlo Park, CA(2)Newport, CA(2)Pleasant Hill, CA(2)Porter Ranch, CA(2)San Clemente, CA(2)San Fernando, CA(2)San Gabriel, CA(2)San Pablo, CA(2)Seal Beach, CA(2)Sepulveda, CA(2)Solana Beach, CA(2)Tracy, CA(2)Visalia, CA(2)Winnetka, CA(2)Alameda, CA(1)Arcata, CA(1)Atascadero, CA(1)Benicia, CA(1)Bonita, CA(1)Brawley, CA(1)Calabasas, CA(1)Capitola, CA(1)Cathedral City, CA(1)City of Industry, CA(1)Colusa, CA(1)Commerce, CA(1)Corona del Mar, CA(1)Danville, CA(1)Durate, CA(1)El Monte, CA(1)Fairfield, CA(1)Foster City, CA(1)Freedom, CA(1)Freemont, CA(1)Fruitdale, CA(1)Goleta, CA(1)Granite Bay, CA(1)Grass Valley, CA(1)Grove, CA(1)Hayward, CA(1)Healdsburg, CA(1)Hollywood, CA(1)Iowa City, CA(1)Ladera Ranch, CA(1)Livermore, CA(1)Lompoc, CA(1)Los Altos Hills, CA(1)Los Angles, CA(1)Manteca, CA(1)Montecito, CA(1)Moorpark, CA(1)Mount Shasta, CA(1)Multiple Locations, CA(1)National City, CA(1)Nipomo, CA(1)Oroville, CA(1)Placentia, CA(1)Placerville, CA(1)Reseda, CA(1)Rolling Hills, CA(1)Rosemead, CA(1)Rowland Heights, CA(1)San Anselmo, CA(1)San Deigo, CA(1)San Franciso, CA(1)San Pedro, CA(1)San Ysidro, CA(1)Scotts Valley, CA(1)Shandon, CA(1)Sherman, CA(1)Sonoma, CA(1)Temple City, CA(1)Templeton, CA(1)Torrence, CA(1)Travis AFB, CA(1)Travis Air Force Base, CA(1)Turlock, CA(1)Ukiah, CA(1)Union City, CA(1)Watsonville, CA(1)Willits, CA(1)Yuba City, CA(1)

Related healthcare resources in California

Trials by condition in California