Sorafenib studied for treatment of desmoid tumors

Desmoid tumors (also called aggressive fibromatosis) are noncancerous growths that occur in the connective tissue, most often in the abdomen, arms and legs. If desmoid tumors grow, they can affect nearby tissues and organs, causing symptoms and complications.

A randomized phase III trial showed sorafenib significantly shrunk tumors, compared to placebo, in patients with desmoid tumors. Tumor shrinkage was also seen with placebo, as desmoid tumors can sometimes shrink without treatment.

What Patients Need to Know

Sorafenib, a tyrosine kinase inhibitor, is FDA approved for the treatment of certain cancers, including liver, kidney and thyroid. Sorafenib works by blocking the action of proteins that promote the growth of new blood vessels; these blood vessels carry oxygen, minerals, and other nutrients that tumors need to grow. Sorafenib also blocks some of the proteins on cancer cells that help them grow and multiply.

Regorafenib shows promise for treatment of metastatic osteosarcoma

The phase II trial REGOBONE evaluated the effectiveness and safety of the targeted therapy regorafenib for the treatment of metastatic osteosarcoma.

Regorafenib is a kinase inhibitor. Kinase proteins are substances near the surface of cells that send important signals to the cell’s control center; by doing so, they can help tumor cells grow.

What Patients Need to Know

In the treatment of metastatic osteosarcoma after the failure of conventional chemotherapy, regorafenib demonstrated promising activity with acceptable toxicity, justifying further trials. In another phase II trial, regorafenib failed to improve outcomes (compared to placebo) in the treatment of advanced or metastatic liposarcoma that is not responding to treatment (is refractory).

Investigational drugs studied in treatment of KIT mutations in gastrointestinal stromal tumors

An estimated 80 percent of gastrointestinal stromal tumors (GISTs) have a mutation of the KIT gene, resulting in an over-production of a protein which can cause cancer cells to grow.

The results of a phase I dose escalation trial suggested that the combination of the investigational drugs PLX9486 and pexidartinib showed some effectiveness against a range of KIT mutations in patients with GIST.

What Patients Need to Know

Both PLX9486 and pexidartinib are tyrosine kinase inhibitors (TKIs). The trial participants were people whose GIST had progressed after being treated with imatinib or other TKIs.
The trial found that the combination of PLX9486 and pexidartinib was generally well tolerated, with mild and reversible side effects.

Study investigated use of apatinib for Ewing sarcoma

A retrospective analysis investigated the effectiveness and safety of apatinib, a VEGFR-2 inhibitor, in patients with advanced Ewing sarcoma (ES).

The results of the analysis suggested that apatinib may be effective as a second- or first-line treatment option for advanced ES patients, particularly in cases resistant to chemotherapy.

What Patients Need to Know

Further retrospective studies, which include more cases with longer follow-up times, are necessary to determine the clinical effectiveness of apatinib in treating Ewing sarcoma.