Aiming for Immunity: New Therapies in Sights

Anita T. Shaffer @Shaffer1 | July 14, 2011
As a result of the drug’s success, “we’re beginning to see more broad acceptance of immunotherapies in the oncology community at large, and it certainly defines immunotherapy as a treatment modality for cancer,” Hoos noted. “It makes it more likely there will be further investigations that are successful.”

monoclonal antibodies in
cancer immunotherapy

Illustration depicts a spacefill model of an antibody. The use of monoclonal antibodies in cancer immunotherapy has been highly successful.

Researchers Battled Skepticism

If success breeds success for immunotherapy approaches this time around, past disappointments have made researchers feel as though they were fighting for acceptance of their theories.

The cycle has been one of soaring hopes dashed by clinical realities. In the 1970s, developing monoclonal antibodies (mAbs) generated so much excitement that they were touted as “magic bullets,” according to a report from the Cancer Research Institute and MD Becker Partners LLC (Report).

Disappointment set in when it took until 1997 for the fi rst drug in the class, rituximab (Rituxan), to gain approval. Now, the passive immunotherapy drugs are “one of the most successful therapeutic classes,” the report notes.

Likewise, active immunotherapies at first proved disappointing.

“In part, those disappointments have come from some of the vaccine approaches that were promising in the early going and did not pan out in clinical trials,” said Gajewski.

He said, though, that when bright prospects dimmed, “it forced researchers to try and fi gure out the mechanisms,” and that has in turn helped identify barriers to immune functions, which are now being targeted.

At its heart, immunotherapy is defined as biologic therapy that uses parts of the immune system to fight cancer, with therapy approaches broadly defined as active, passive, and targeted immunotherapies, according to the American Cancer Society.

FDA-Approved Cancer Immunotherapies

Monoclonal Antibodies
Disease State
Approval
 
Rituximab (Rituxan)
 
Non-Hodgkin lymphoma (NHL)
Chronic lymphocytic leukemia (CLL)
1997
2010
 
Trastuzumab (Herceptin)
 
Breast cancer
Stomach cancer
1998
2010
 
Gemtuzumab
ozogamicin (Mylotarg)
Acute myelogenous leukemia
 
2000†
 
 
Alemtuzumab (Campath)
CLL
2001
 
Ibritumomab tiuxetan* (Zevalin)
NHL
2002
 
Tositumomab* (Bexxar)
NHL
2003
 
Cetuximab (Erbitux)
 
Colorectal cancer
Head & neck cancers
2004
2006
 
Bevacizumab (Avastin)
 
 
 
 
Colorectal cancer
Non-small cell lung cancer
Breast cancer
Glioblastoma
Renal cell carcinoma (RCC)
2004
2006
2008
2009
2009
 
Panitumumab (Vectibix)
Colorectal cancer
2006
 
Ofatumumab (Arzerra)
CLL
2009
 
Denosumab (Xgeva)
Cancer spread to bone
2010
 
Ipilimumab (Yervoy)
Melanoma
2011
 
Vaccines‡
Sipuleucel-T (Provenge)
Prostate cancer
2010
 
Cytokines/Proteins
Interleukin-2 (IL-2)
(aldesleukin, Proleukin)
(denileukin diftitox, Ontak)

 RCC, melanoma
Cutaneous T-cell lymphoma

1992, 1998
1999
 
Interferon alfa-2b (Intron A)
 
 
Hairy cell leukemia
Melanoma
Follicular lymphoma
1986
1995
1997
 
Other Adjuvants
Bacille Calmette-Guérin(TICE BCG)
Bladder cancer
1998
 
Immunomodulating Agents
Thalidomide (Thalomid)
Lenalidomide (Revlimid)
Multiple myeloma (MM)
MM
1998**
2005
 
Sources: American Cancer Society, Drugs @ FDA database, prescribing information for individual drugs.

* Conjugated monoclonal antibodies that are radiolabeled
† Approval withdrawn as of October 15, 2010; this drug is only available for use within a clinical trial
Indication under FDA review
‡ Human papillomavirus and hepatitis B vaccines target viruses that can cause cancer and are not considered immunotherapy vaccines
** Initial FDA approval for treating erythema nodosum leprosum
While many forms of immunotherapy are under investigation, the society said FDA-approved options include 12 mAbs, 2 cytokines/proteins, and 2 immunomodulating agents.


View Conference Coverage
Online CME Activities
TitleExpiration DateCME Credits
Publication Bottom Border
Border Publication