Merrimack Pharmaceuticals

Closed portfolio with an early-phase archive tilt

According to ClinicalTrials.gov-derived indexes, Merrimack Pharmaceuticals sits in the top decile of US sponsors by registered trial count (#696 of 15,742 sponsors by registered trial count).

22 total trials none currently recruiting 19 completed early-phase tilt top decile by trial count

Merrimack Pharmaceuticals: 22 sponsored US clinical trials, none currently recruiting.

Merrimack Pharmaceuticals sponsors 22 registered US clinical trials on ClinicalTrials.gov, none currently recruiting, and 19 completed. 1 of these trials are in Phase 3-4 (later-stage) and 21 in Phase 1-2 (earlier-stage). The most-studied condition in this pipeline is Her2 Amplified Solid Tumors, with 1 trials.

Top-decile sponsor footprint

Merrimack Pharmaceuticals ranks in the top decile of sponsors by registered trial count (#696 of 15,742 sponsors by registered trial count). Volume at this scale usually reflects a long institutional pipeline, read phase tilt and therapeutic areas below before treating it as current-year activity.

Trial completion reliability score

D 55/100

19 of 22 decided trials (Completed vs. Terminated on ClinicalTrials.gov) reached their planned completion (86.4%), vs. national p10 68.4% / p90 100% among 1,234 sponsors with at least 10 decided trials. Still-open trials (Recruiting, Active-not-recruiting, Not-yet-recruiting) are excluded since they have not reached an outcome yet.

Indexed trials (enrollment closed)

22 total, page 1 of 1

TERMINATED Phase 1

Phase 1 Combination Study of MM-151 With MM-121, MM-141, or Trametinib

NCT02538627

COMPLETED Phase 2

A Phase 2 Study of MM-141 Plus Nab-paclitaxel and Gemcitabine in Front-line Metastatic Pancreatic Cancer

NCT02399137

TERMINATED Phase 2

MM-302 Plus Trastuzumab vs. Chemotherapy of Physician's Choice Plus Trastuzumab in HER2-Positive Locally Advanced/Metastatic Breast Cancer Patients

NCT02213744

TERMINATED Phase 2

A Study of MM-111 and Paclitaxel With Trastuzumab in Patients HER2 Positive Carcinomas of the Distal Esophagus, Gastroesophageal (GE) Junction and Stomach

NCT01774851

COMPLETED Phase 1

A Phase 1 Study of MM-141 in Patients With Advanced Solid Tumors

NCT01733004

COMPLETED Phase 1

Safety Study of the Drug MM-151 in Patients With Advanced Solid Tumors Resisting Ordinary Treatment

NCT01520389

COMPLETED Phase 3

Study of MM-398 With or Without 5-FU/LV, Versus 5-FU/LV in Patients With Metastatic Pancreatic Cancer

NCT01494506

COMPLETED Phase 1

A Safety Study of MM-121 With Cetuximab and Irinotecan in Patients With Advanced Cancers

NCT01451632

COMPLETED Phase 1

Safety Study of MM-121 in Combination With Multiple Anticancer Therapies in Patients With Advanced Solid Tumors

NCT01447225

COMPLETED Phase 2

A Study of MM-121 With Paclitaxel in Platinum Resistant/ Refractory Advanced Ovarian Cancers

NCT01447706

COMPLETED Phase 2

A Trial of Preoperative MM-121 With Paclitaxel in HER2-negative Breast Cancer

NCT01421472

COMPLETED Phase 1

A Study of MM-111 in Combination With Multiple Treatments in Patients With HER2 Positive Cancer

NCT01304784

COMPLETED Phase 1

A Study of MM-121 in Combination With Paclitaxel in Patients With Advanced Gynecologic and Breast Cancers

NCT01209195

COMPLETED Phase 2

Trial of Exemestane +/- MM-121 in Postmenopausal Women With Locally Advanced or Metastatic Estrogen Receptor Positive and/or Progesterone Receptor Positive Her2 Negative Breast Cancer

NCT01151046

COMPLETED Phase 1

MM-111 in Combination With Herceptin in Patients With Advanced Her2 Amplified, Heregulin Positive Breast Cancer

NCT01097460

COMPLETED Phase 1

A Study of MM-121 Combination Therapy in Patients With Advanced Non-Small Cell Lung Cancer

NCT00994123

COMPLETED Phase 1

A Study of MM-111 in Patients With Advanced, Refractory Her2 Amplified, Heregulin Positive Cancers

NCT00911898

COMPLETED Phase 1

Phase I Safety Study of the Drug MM-121 in Patients With Advanced Solid Tumors Resisting Ordinary Treatment

NCT00734305

COMPLETED Phase 2

A Phase 2 Study to Evaluate the Efficacy and Safety of 60mg of MM-093 in Patients With Active Rheumatoid Arthritis

NCT00458146

COMPLETED Phase 2

Phase 2 Study of MM-093 to Treat Patients With Uveitis

NCT00444743

COMPLETED Phase 2

Safety and Efficacy Study of MM-093 in Patients With Chronic Plaque Psoriasis

NCT00147329

COMPLETED Phase 2

Efficacy Study of MM-093 in Rheumatoid Arthritis Patients on Methotrexate (MTX)

NCT00105976

How the Merrimack Pharmaceuticals early-phase archive is shaped

22 indexed studies, none listed as recruiting (0% open); 19 completed (86%).

Phase mix: 1 late (III/IV) vs 21 early (I/II) (early-phase heavy).

Top condition: Her2 Amplified Solid Tumors (1 trial), 9 others listed.

How to read a closed sponsor archive

When recruiting_count is zero, the indexed set is completed or otherwise not open. Phase tilt still describes where archived studies sat on the investigational pathway. Re-check ClinicalTrials.gov before acting.

Merrimack Pharmaceuticals: archived-pipeline peers nationwide

Peers matched on 22 indexed studies with no current recruiting: volume and archive shape, not condition overlap.

Merrimack Pharmaceuticals sits at or above the median trial volume and at or above the median recruiting share among these 9 nationwide peers -- the two do not always move together. Source: ClinicalTrials.gov (2026-08-08 snapshot). 2×2 strategic matrix plotting 9 entities by Total trials (X) and Recruiting share (Y), with a crosshair dividing the plot into four quadrants. Higher volume & more openFocused & more openHigher volume, mostly closedSmaller & mostly closed 0510152025 0%5%10%15% Total trials Recruiting share Merrimack PharmaceuticalsAlaunos TherapeuticsAlexza PharmaceuticalsCalithera BiosciencesFate Therapeutics10xBio22nd Century Group23andMe3-C Institute for Social Development
Merrimack Pharmaceuticals sits at or above the median trial volume and at or above the median recruiting share among these 9 nationwide peers -- the two do not always move together. Source: ClinicalTrials.gov (2026-08-08 snapshot).

Merrimack Pharmaceuticals sits at or above the median trial volume and at or above the median recruiting share among these 9 nationwide peers -- the two do not always move together.

Sponsors near 22 archived trials

Sponsors with similar archive density (± trial count)

What to do with this Merrimack Pharmaceuticals page

22 registered trials is a research-attention snapshot, not an endorsement of Merrimack Pharmaceuticals or any single study.

  • None of Merrimack Pharmaceuticals's trials are currently recruiting in this registry; that can change as new trials post, or check the broader research index. Browse research indexes
  • Her2 Amplified Solid Tumors is the condition Merrimack Pharmaceuticals studies most, compare against other sponsors active in the same condition before evaluating a specific study. See Her2 Amplified Solid Tumors trials
  • Bring the specific trial ID (NCT number) to your own doctor before enrolling, this page is a directory, not medical guidance. Read the trial-finding guide

Trial and recruiting counts reflect ClinicalTrials.gov registry status as of the data vintage above; individual trial eligibility and enrollment status can change.

Every figure on PlainTrial is rendered directly from the ClinicalTrials.gov registry, no number is typed in by an editor. Merrimack Pharmaceuticals pipeline card: 22 registered trials from official public datasets. See our editorial standards & corrections policy, the methodology behind these numbers, the data changelog, or report a data error.