The Third Rail of the CRISPR Moonshot: Minding the Germline

Biopolitical Times

As the 2015 news cycle ground down and rebooted for the new year, a wide swath of news publications—industry, research, scientific, and popular—declared CRISPR gene editing to be one of 2015’s biggest stories. In the new year, an ongoing CRISPR concern is how we can strengthen and brighten the line of policy and practice that cautions against creating genetically modified human babies.

Much of the news since the #GeneEditSummit in December has focused on a very different application of CRISPR: producing therapies for patients living with genetic conditions. Jaw-dropping investment news is issuing forth as multiple biotech firms team up with drug companies and venture capitalists to bring the CRISPR moonshot of gene-editing therapies into view.

While CRISPR coverage doesn’t always make it clear, many of the leading gene-editing companies have clearly stated that they’re aiming to treat genetic disease in one consenting patient at a time, not on a population level, and not in a fertility clinic for prospective parents seeking to tailor the genetic variants they pass on to their future children. Several key players in this lab-to-market push have spoken out forcefully:

Sangamo Biosciences (key figure(s): Edward Lanphier, CEO/president)

Early in 2015 as rumors were circulating that scientists were experimenting with the CRISPR/Cas9 technology on human embryos, some biotech figures stepped up proactively to make their concerns heard.  Edward Lanphier, CEO/president of Sangamo Biosciences (using older gene-editor Zinc Fingers to develop HIV/AIDS gene therapies), published an article in Nature with colleagues from the Alliance for Regenerative Medicine entitled “Don’t edit the human germline.” The article describes the use of CRISPR  gene editing in embryos to create edited humans as “dangerous and ethically unacceptable” and says “[w]e are concerned that a public outcry about such an ethical breach could hinder a promising area of therapeutic development, namely making genetic changes that cannot be inherited.” Recently, Sangamo announced that the FDA had approved its new hemophilia drug application for what could be the first in vivo clinical trial of a gene editing technology.

Intellia Therapeutics, Caribou Biosciences (Jennifer Doudna) and CRISPR Therapeutics (Emmanuelle Charpentier)

Intellia Therapeutics and CRISPR Therapeutics, two companies founded by CRISPR co-discoverers, released a statement [pdf] on the first day of the National Academies’ summit on human gene editing that said in part:

[G]ermline gene editing is outside of the scope of our companies’ research and development. We are dedicated to discovering and developing gene editing-based treatments for serious diseases using only non-germline somatic cells. This is the greatest area of patient need, where the benefits and risks are best understood, and where the ethical support is unambiguous. … [W]e are committed to … [r]efraining from directly modifying germline cells, including sperm, egg or embryonic tissue, or developing any clinical applications of germline gene editing.

Jennifer Doudna and Emmanuelle Charpentier have held this view for some time.

A few weeks after the Sangamo et al. Nature article, Doudna joined a cautious-yet-optimistic statement with other scientists that asked for a pause in CRISPR germline research in order to engage in broad public debate. In Doudna’s personal and professional capacity since “A prudent path forward for genomic engineering and germline genetic modification,” [pdf] she has expressed more extensive reservations. There’s the Hitler dream she recalled to Michael Specter in The New Yorker, and the article she published in Nature on the first day of the #GeneEditSummit that argued against editing the human germline because of “the unknown social consequences” and our limited knowledge of the “technology” and “the human genome.”

Emmanuelle Charpentier has gone further, telling BBC in September “Personally I don't think that it is acceptable to manipulate the human germline for the purposes of changing some genetic traits that will be transmitted over generations,” and telling New Scientist in December: “I hope that using the technology with the idea of changing human characteristics will not be pursued. …  Philosophically and sociologically speaking, I have lots of issues with this.”

In New Scientist, Charpentier also noted, “[T]here is money involved, whether I like it or not.” Indeed. A few weeks later news broke that Charpentier’s company CRISPR Therapeutics had penned a five-year $350 million joint venture with German drug firm Bayer to develop “new delivery technologies” to overcome a big gene therapy obstacle: getting CRISPR into the cells of targeted tissues. Doudna’s firms, meanwhile, are also teaming up with major investors. Caribou has formed “strategic alliance[s]” with two giants, chemical manufacturer DuPont to develop a variety of fields including industrial, agricultural, animal and antimicrobial applications of CRISPR, and drug developer Novartis which will be working with Caribou’s offshoot company Intellia to pursue human therapeutics, while also collaborating with Caribou in research.

Editas Medicine (Feng Zhang, CEO Katrine Bosley)

The first CRISPR company to file to go public still hasn’t made it clear where it stands on the germline controversy. Asked by Nature in May [pdf], Editas co-founder and CRISPR co-discoverer Feng Zhang noted, “[G]iven that many diseases might be treatable through somatic cell genome editing, it is unclear whether germ line editing is an appropriate solution.” In the same interview, Editas CEO Katrine Bosley stated,

The current question about CRISPR and germline engineering is far more complex [than mitochondrial replacement or 3 person IVF], and we don’t have a sense of the breadth of the implications, and we don’t understand the risks well. The technology’s progress now demands us to confront these questions, but that can’t be done quickly.

In recent coverage, Zhang is paraphrased as saying that “the importance of germline editing varies between groups of people, such as potential parents and policy-makers,” while noting that as a researcher, “we are not ready to use [CRISPR] for medical treatment, because there are issues with specificity and efficiency.” Yet neither Zhang nor Editas has voiced principled objections to allowing scientists, private companies, or others to engineer the genes we pass on to future generations. With money rolling in, they may not be worried about the fears of investors, but as a company racing to be the first to begin human clinical trials of a CRISPR gene therapy, they should probably be concerned about how the public will view their ambivalence on the germline question.

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Minding the Germline

Gene therapy companies know that there are numerous obstacles to overcome if they are to translate shiny and powerful new nano-engineering tools like CRISPR into accessible medical treatments down the line. Many remember Jesse Gelsinger, a teenager who died after a gene therapy trial gone wrong, and are aware that this tragedy cautions against the breakneck speed that the market dynamics of drug development engender. Researchers working in stem cell therapeutics—many of whom, like the scientists and biotech figures cited above, have called for a moratorium on germline applications of CRISPR—are also familiar with this tale.

Concerns about the safety and effectiveness of this new kind of gene therapy have been voiced by many, though hyperbole about Eradicating! All! Genetic! Disease! can still be found. Less widely acknowledged are questions about whether any treatments that are successfully developed will be affordable. In California, billions of dollars of taxpayer money have been invested into the California Institute for Regenerative Medicine (CIRM) in hopes of developing hugely hyped but so far nonexistent therapies; after ten years, two late-stage clinical trials are ongoing and may produce medically relevant results, but at sky-high prices.

While CRISPR is ubiquitous in some circles, it still hasn’t hit the public fan like stem cells did back in the 2004 presidential election. It is heartening to see biotech companies come out in very public ways against research and development aimed at engineering the human germline, but questions remain. Will this long-anticipated reboot of gene therapy deliver safe and effective treatments? Will the hundreds of millions of invested dollars—private money to be sure, but money chasing a scientific advance made in large part at public universities—lead to treatments that are accessible and affordable?

Previously on Biopolitical Times:

Image via Flickr/Richard Masoner