California Clinical Trials Report — July 2026

People in California who are considering a clinical trial should act quickly if they match a study nearing enrollment closure: 325 trials are expected to close within the next 90 days. Among them, 63 accept healthy volunteers. The largest groups of closing studies involve breast cancer and prostate cancer, with 9 trials each, followed by cancer overall (7), healthy participants (6), and ovarian cancer (6).

California also added 135 recruiting trials in July, down from 148 in June and 186 in May. Despite the month-to-month slowdown, the state remains one of the country’s largest research markets, with 5,467 trials recruiting across 302 cities and 5,149 research sites.

Closing enrollment creates an immediate opportunity

Patients with cancer may find the most time-sensitive openings. In addition to breast and prostate cancer, studies closing soon address multiple myeloma (4 trials), non-small cell lung cancer (4), endometrial cancer (4), pancreatic cancer (4), and advanced solid tumors (4). Anyone considering a trial should confirm current enrollment status directly, since a study’s projected closing date can change and screening may take time.

• Breast cancer (9 closing-soon trials)
• Prostate cancer (9)
• Cancer, unspecified (7)
• Healthy participants (6)
• Ovarian cancer (6)
• Multiple myeloma, non-small cell lung cancer, endometrial cancer, pancreatic cancer, and advanced solid tumor (4 each)

Healthy adults have a particularly narrow window in some studies. Six closing-soon trials specifically list healthy participants among their conditions, while 754 healthy-volunteer studies are recruiting statewide overall. Of the new July trials, 38 accept healthy volunteers, including studies involving behavioral research, psychology, prevention, and other non-treatment questions.

Obesity, mental health, and prevention shape July’s new research

The month’s new studies cover a broad mix of conditions. Obesity led the list with 5 new trials, followed by overweight, post-traumatic stress disorder, schizophrenia, and stroke with 3 each. Menopause and obstructive sleep apnea each appeared in 2 new trials, while two studies listed healthy participants as a central population.

• Obesity (5 new trials)
• Overweight, PTSD, schizophrenia, and stroke (3 each)
• Post-traumatic stress disorders, relapsed or refractory multiple myeloma, menopause, and obstructive sleep apnea (2 each)
• Healthy participants (2)

Drug studies were the most common intervention type, accounting for 58 new trials. Behavioral research followed with 25, while other studies included devices (21), biological interventions (9), procedures (9), and dietary supplements (7). This mix gives prospective participants options beyond experimental medicines, including digital programs, devices, lifestyle interventions, and observational or behavioral studies.

Standout new studies from major sponsors and California institutions

Several new trials are notable for their scale, study phase, or sponsor. Amgen’s Phase 3 MARITIME-1-EXTENSION study, NCT07684235, plans to enroll 3,200 people with obesity or overweight to evaluate the long-term efficacy, safety, and tolerability of maridebart cafraglutide. It extends an earlier trial and may appeal to people who meet weight-related eligibility requirements.

Sanofi is sponsoring NCT07734649, a Phase 1/2 study of an RSV and human metapneumovirus vaccine candidate in adults age 60 and older. The trial plans to enroll 2,400 participants and will examine immune response and safety. Older adults are a substantial part of California’s new-trial landscape: 108 July studies include older adults in their eligibility criteria.

• NCT07684235 — Amgen’s Phase 3 extension study of maridebart cafraglutide for obesity or overweight.
• NCT07734649 — Sanofi’s Phase 1/2 RSV and human metapneumovirus vaccine study for adults 60 and older.
• NCT07679282 — A Phase 4 comparison of positive airway pressure, a dental device, and atomoxetine-oxybutynin for obstructive sleep apnea, targeting 2,400 participants.
• NCT07725250 — A behavioral randomized trial evaluating AI and personalized medicine approaches to reducing cardiovascular risk, with a planned enrollment of 3,000.
• NCT07687238 — UCSF’s Social Needs Assistance for Hospitalized Kids Trial, enrolling 1,880 participants to study ways of connecting families with social and economic support.

University-based researchers are especially active in studies involving young people and online behavior. USC is sponsoring NCT07694739, which examines how e-cigarette influencer marketing affects adolescents’ perceptions, and NCT07721883, which studies social-media messages about non-combustible tobacco products among adolescents and young adults. Stanford is sponsoring NCT07740148, an online randomized trial comparing immediate psychological responses to human-created and AI-generated art. These three studies plan to involve thousands of participants, although eligibility and recruitment may extend beyond California because participants are recruited nationally or online.

Research opportunities cluster in major metropolitan areas

New trial activity is concentrated in California’s largest research and medical centers. Los Angeles led with 25 new trials, followed by San Francisco (22) and San Diego (16). Duarte and Palo Alto each recorded 10, while Sacramento and La Jolla each had 8. Stanford and Anaheim had 7 apiece, and Orange added 5.

• Los Angeles — 25 new trials
• San Francisco — 22
• San Diego — 16
• Duarte and Palo Alto — 10 each
• Sacramento and La Jolla — 8 each
• Stanford and Anaheim — 7 each
• Orange — 5

The distribution shows a strong metropolitan concentration, particularly around Southern California, the Bay Area, and major university campuses. At the same time, the state’s 302 recruiting cities indicate that opportunities are not limited to one corridor. People should search by both condition and travel radius, since some trials may have only one California site even when the overall study is large.

Who should look now?

Families may find new options among 22 July trials that include children. There are also 10 female-only and 3 male-only studies. Older adults appear in 108 new-trial eligibility criteria, including the Sanofi vaccine study and other age-related research.

Academic and public institutions remain prominent sponsors. UCSF opened 10 new trials, Stanford University opened 7, and the VA Office of Research and Development also opened 7. AstraZeneca sponsored 6, UC San Diego sponsored 5, City of Hope and USC sponsored 4 each, and UC Davis sponsored 3. Across sponsor categories, 63 new trials were industry-sponsored, 61 were classified as other, and federal sponsors accounted for 8.

For patients with cancer, healthy adults, older people, parents, and residents near the state’s major research hubs, July is a month to check eligibility without delay. With enrollment deadlines approaching and new obesity, mental-health, vaccine, sleep-apnea, and behavioral studies opening, California’s research pipeline is positioned to continue changing through the rest of 2026.