Macular Degeneration—Is Gene Therapy the Answer?

INTRODUCTION

There is good news on the horizon regarding age-related macular degeneration (AMD), Stargardt disease (the juvenile version) and related retinal pathologies.  Although gene therapy is not new, the ways that it may enhance treatment options for these and other eye diseases is, to put it mildly, astounding.  

WHY THE EYES ARE ALMOST PERFECTLY SUITED FOR GENE THERAPY

Unfortunately, not every part of the body is ideal for gene therapy; furthermore, genes responsible for diseases have first to be identified and studied.   When it comes to gene therapy, however, the eyes appear to be ideal candidates. 

The eyes, posit top ophthalmologists, are ideally suited for gene therapy because . . .

• They are unlikely to prompt a treatment-halting/compromising immunologic response to the therapy—one of the few organs in the body about which this may be said.
• Due to their limited/confined space, only small dosages of vectors/medicine may be necessary.
• They may not be subject to the toxicity dangers that sometimes accompany gene therapy.
• Therapy may include localized treatment minus intravenous delivery, reducing dangers of systemized absorption/toxicity.
• The progress of localized ocular treatment lends itself well to observation/monitoring. 

SHOULD YOU BE EXCITED ABOUT THE NEW DEVELOPMENTS IN GENE THERAPY?

Although much of the exciting progress that has been made in retinal disease treatment (e.g. AMD) understanding and potential treatment options is “clouded” by scientific mumbo-jumbo, your eye care doctor is bound to be well-equipped and ready to keep you well-informed.

 Here are some facts worth celebrating: 

--Some clinical trials involving humans are already under way. Clinical trials come only after lab research establishes the need or viability for human-involved experimentation.  One such set of trials involves StarGen, run and supervised by Oxford BioMedica and funded by the Foundation Fighting Blindness.  Other trials are being funded by the US government.

--It has been established that those getting macular degeneration gene therapy are tolerating the treatment well; this only adds to the efficacy and safety of the treatments options being developed.

--A protein, IRBP, which appears to be connected with vitamin-A-transportation use and the development of retinal disease, has been identified and is presently being studied; if related to the disease, the discovery may propel treatment options. 

--The methods used to deliver the vectors to the diseased tissue are steadily being improved.

--Pharmaceutical agents that must presently accompany or aid gene therapy are constantly being developed and/or improved—e.g., pegaptanib (Genentech), ranibiz-umab, and aflibercept (Regeneron). 

CONCLUSION

As of today, 1 out 150 people in the US suffers or will suffer from retinal disease or complications.  Because of these numbers and because eyesight is so important, ophthalmologists recognize and insist that all avenues of treatment be looked into aggressively. 

Gene therapy continues to be one of the most promising treatment modalities to date.  Anyone who looks at the facts can easily “see” that!

Copyright, 2018.  Fred Fletcher.  All rights reserved. 

REFERENCES & RESOURCES

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