I think they cited that standard of care for non-small cell lung cancer is changing, so it's harder to recruit patients, and as Taxol is not as widely used for first line therapy, it's not worth wasting time and resources on this approach.
per earnings call:
After careful consideration on how best to develop PEGPH20 an advance non-small cell lung cancer giving the evolving standard a care we have made the decision to discontinue further enrollment in the primal study and to initiate closer activities for that trial.
While this was not an easy decision to make the rapidly evolving standard of care for patients with non-small care lung cancer has resulted in the use of docetaxel at a linked or lined therapy. In turn this has made it difficult to execute the study as originally designed and to test it underlying research hypothesis.
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