Biotech week ahead, May 3

 Biopharma stocks experienced volatility in the week ended April 30, as stocks reacted to earnings, data readouts and a handful of FDA decisions.

Earnings prints from big name pharma companies, including Merck & Co., Inc. MRK 1.13%, Amgen Inc. AMGN 2.1%, Eli Lilly and Company LLY 0.3% and Novartis AG NVS 0.91%, were uninspiring.

Among Food and Drug Administration decisions scheduled for the week, Sol-Gel Technologies Ltd. 

SLGL 2.67% said the FDA is yet to get back on a decision, Protalix BioTherapeutics, Inc. PLX 4.81% received a complete response letter, and Ardelyx, Inc. ARDX) communicated a three-month delay.

Adverum Biotechnologies, Inc. ADVM 1.83% suffered a setback following the reporting of a serious adverse event in a study evaluating its investigational gene therapy for diabetic macular edema.

Two biopharma companies debuted on the Nasdaq, raising a combined $230.5 million in gross proceeds.

Here are the key catalysts for the unfolding week:

Conferences

The American Society for Aesthetic Plastic Surgery, or ASAPS, Aesthetic Meeting 2021 (Miami, Florida): April 29-May 3

American Psychiatric Association, APA, 2021 Annual Meeting (virtual): May 1-3

Association for Research In Vision and Ophthalmology, or ARVO, 2021 Virtual Meeting: May 1-7

World Vaccine Congress Washington (virtual meeting): May 4-6

European Society for Medical Oncology, ESMO, Breast Cancer Virtual Congress 2021: May 5-8

Adcom Calendar

FDA's Arthritis Advisory Committee is scheduled to meet Thursday to discuss ChemoCentryx, Inc.'s CCXI 7.4% NDA for avacopan oral capsules, for the treatment of anti-neutrophil cytoplasmic antibody-associated vasculitis. The meeting is scheduled between 10 a.m. and 4:15 p.m.

Clinical Readouts

Vaxart, Inc. VXRT 17.05% is scheduled to present on Monday new data comparing the T-cell responses generated from its VXA-CoV2-1 vaccine with those of other vaccines. (12 p.m.)

ARVO Presentations

Ocular Therapeutix, Inc. (NASDAQ: OCUL): Phase 1 data for an intracameral travoprost hydrogel-based implant for the treatment of primary open angle glaucoma and ocular hypertension (Monday, 11:15 a.m. to 1 p.m.)

Adverum: Phase 1 data for intravitreal gene therapy with ADVM-022 for neovascular age-related macular degeneration (Monday, 4:30-6 p.m.)

Applied Genetic Technologies Corporation AGTC 1.63%: six-month findings from a Phase 1/2 clinical study of subretinal gene therapy drug AGTC-501 for X-Linked retinitis pigmentosa (Monday, 4:30-6 p.m.) and 12-month findings from 2 Phase 1/2 clinical studies of subretinal gene therapy drugs for achromatopsia (Thursday, 5:15-6:45 p.m.)

Palatin Technologies, Inc. PTN 1.61%: data from the Phase 2 study of PL9643 in dry eye disease (Thursday, 11:15 a.m. to 1 p.m.)

ESMO Meeting

Veru Inc. VERU 3.91%: Clinical results from the Phase 2 clinical study of enobosarm in heavily pretreated women with AR+ER+HER2- advanced breast cancer

Earnings

Monday

Karyopharm Therapeutics Inc. KPTI 2.3% (before the market open)
GlycoMimetics, Inc. GLYC 4% (before the market open)
SI-BONE, Inc. SIBN 0.91% (after the close)
Myriad Genetics, Inc. MYGN 0.03% (after the close)
Ligand Pharmaceuticals Incorporated NASDAQGND (after the close)
QIAGEN N.V. QGEN 0.62% (after the close)

Tuesday

Pfizer Inc. PFE 0.03% (before the market open)
Seres Therapeutics, Inc. MCRB 1.75% (before the market open)
Sage Therapeutics, Inc. SAGE 0.15% (before the market open)
Jounce Therapeutics, Inc. JNCE 0.11% (before the market open)
Incyte Corporation INCY 0.58% (before the market open)
Concert Pharmaceuticals, Inc. CNCE 0.24% (before the market open)
Repligen Corporation RGEN 0.67% (before the market open)
Catalent, Inc. CTLT 1.46% (before the market open)
Lantheus Holdings, Inc. LNTH 0.77% (before the market open)
Neuronetics, Inc. STIM 3.58% (before the market open)
Bausch Health Companies Inc. BHC 1.44% (before the market open)
Zimmer Biomet Holdings, Inc. ZBH 0.85% (before the market open)
Pacira BioSciences, Inc. PCRX 1.59% (before the market open)
Agile Therapeutics, Inc. AGRX 1.65% (after the close)
Aquestive Therapeutics, Inc. AQST 3.78% (after the close)
Atara Biotherapeutics, Inc. ATRA 3.23% (after the close)
Aptose Biosciences Inc. APTO 0.18% (after the close)
Aziyo Biologics, Inc. AZYO 5.15% (after the close)
Arrowhead Pharmaceuticals, Inc. ARWR 3.96% (after the close)
Theravance Biopharma, Inc. TBPH 0.5% (after the close)
Exact Sciences Corporation EXAS 0.9% (after the close)
Jazz Pharmaceuticals plc JAZZ 0.81% (after the close)
Silk Road Medical, Inc SILK 1% (after the close)
Ultragenyx Pharmaceutical Inc. RARE 1.65% (after the close)
PTC Therapeutics, Inc. PTCT 3.04% (after the close)
Sangamo Therapeutics, Inc. SGMO 1.01% (after the close)
Penumbra, Inc. PEN 1.19% (after the close)
Inspire Medical Systems, Inc. INSP 1.79% (after the close)
Globus Medical, Inc. GMED 1.1% (after the close)
Esperion Therapeutics, Inc. ESPR 1.32% (after the close)
Deciphera Pharmaceuticals, Inc. DCPH 0.88% (after the close)
Cerus Corporation CERS 2.01% (after the close)
Cytosorbents Corporation CTSO 1.65% (after the close)
Invitae Corporation NVTA 0.26% (after the close)
DURECT Corporation DRRX 0.53% (after the close)

Wednesday

Horizon Therapeutics Public Limited Company HZNP 0.08% (before the market open)
EyePoint Pharmaceuticals, Inc. EYPT 0.83% (before the market open)
Editas Medicine, Inc. EDIT 0.96% (before the market open)
United Therapeutics Corporation UTHR 1.31% (before the market open)
Clovis Oncology, Inc. CLVS 1.33% (before the market open)
Vericel Corporation VCEL 2.13% (before the market open)
10x Genomics, Inc. TXG 0.2% (before the market open)
Passage Bio, Inc. PASG 3.55% (before the market open)
Ionis Pharmaceuticals, Inc. IONS 1.15% (before the market open)
NeoGenomics, Inc. (NEO) (before the market open)
OraSure Technologies, Inc. OSUR 0.22% (after the close)
Ampio Pharmaceuticals, Inc. AMPE 0.53% (after the close)
Arbutus Biopharma Corporation ABUS 1.14% (after the close)
Aerie Pharmaceuticals, Inc. AERI 1.38% (after the close)
Arena Pharmaceuticals, Inc. ARNA 0.06% (after the close)
Aeglea BioTherapeutics, Inc. AGLE 5.24% (after the close)
Allogene Therapeutics, Inc. ALLO 3.31% (after the close)
Adaptive Biotechnologies Corporation ADPT 2.89% (after the close)
AxoGen, Inc. AXGN 0.85% (after the close)
ACADIA Pharmaceuticals Inc. ACAD 0.15% (after the close)
Global Blood Therapeutics, Inc. GBT 2.42% (after the close)
Synthetic Biologics, Inc. SYN 1.41% (after the close)
Neurocrine Biosciences, Inc. NBIX 0.88% (after the close)
Sarepta Therapeutics, Inc. SRPT 0.8% (after the close)
REGENXBIO Inc. RGNX 0.06% (after the close)
Rigel Pharmaceuticals, Inc. RIGL 0.54% (after the close)
Vanda Pharmaceuticals Inc. VNDA 0.54% (after the close)
Ocular Therapeutix, Inc. OCUL 4.07% (after the close)
Glaukos Corporation GKOS 0.8% (after the close)
Celcuity Inc. CELC 0.04% (after the close)
CareDx, Inc CDNA 1% (after the close)
Nevro Corp. NVRO 0.43% (after the close)
Tandem Diabetes Care, Inc. TNDM 2.21% (after the close)
OrthoPediatrics Corp. KIDS 2.24% (after the close)
DiaMedica Therapeutics Inc. DMAC 1.05% (after the close)
Turning Point Therapeutics, Inc. TPTX 2.22% (after the close)
Outset Medical, Inc. OM 3.01% (after the close)
TRACON Pharmaceuticals, Inc. TCON 1.77% (after the close)
Lumos Pharma, Inc. LUMO 0.98% (after the close)
NuVasive, Inc. NUVA 0.38% (after the close)
Supernus Pharmaceuticals, Inc. SUPN 2.62% (after the close)

Thursday

Moderna, Inc. MRNA 1.79% (before the market open)
Intellia Therapeutics, Inc. NTLA 4.13% (before the market open)
Intercept Pharmaceuticals, Inc. ICPT 3.23% (before the market open)
Ironwood Pharmaceuticals, Inc. IRWD 1.95% (before the market open)
Insmed Incorporated INSM 3.35% (before the market open)
Fulcrum Therapeutics, Inc. FULC 0.18% (before the market open)
Endo International plc ENDP 2.72% (before the market open)
Bio-Techne Corporation TECH 1.44% (before the market open)
Harvard Bioscience, Inc. HBIO 3.75% (before the market open)
Athenex, Inc. ATNX 1.23% (before the market open)
Zoetis Inc. ZTS 0.68% (before the market open)
Aldeyra Therapeutics, Inc. ALDX 0.52% (before the market open)
Syros Pharmaceuticals, Inc. SYRS 3.21% (before the market open)
Albireo Pharma, Inc. ALBO 0.47% (before the market open)
BioCryst Pharmaceuticals, Inc. BCRX 4% (before the market open)
Regeneron Pharmaceuticals, Inc. REGN 0.76% (before the market open)
Autolus Therapeutics plc AUTL 2.11% (before the market open)
BioDelivery Sciences International, Inc. BDSI 1.42% (before the market open)
Adaptimmune Therapeutics plc ADAP 2.08% (before the market open)
Axcella Health Inc. AXLA 4.83% (before the market open)
Antares Pharma, Inc. ATRS 1.81% (before the market open)
Agenus Inc. AGEN (before the market open)
ADC Therapeutics SA ADCT 4.12% (before the market open)
Reata Pharmaceuticals, Inc. RETA 0.4% (before the market open)
Epizyme, Inc. EPZM 3.22% (before the market open)
Coherus BioSciences, Inc. CHRS 0.68% (after the close)
Dicerna Pharmaceuticals, Inc. DRNA 0.39% (after the close)
Chiasma, Inc. CHMA 1% (after the close)
Aurinia Pharmaceuticals Inc. AUPH 9.85% (after the close)
Athersys, Inc. ATHX 0.6% (after the close)
Acorda Therapeutics, Inc. ACOR 7.41% (after the close)
Acceleron Pharma Inc. XLRN 0.39% (after the close)
Axonics, Inc. AXNX 0.91% (after the close)
Puma Biotechnology, Inc. PBYI 0.9% (after the close)
Twist Bioscience Corporation TWST 1.75% (after the close)
T2 Biosystems, Inc. TTOO 2.13% (after the close)
ICU Medical, Inc. ICUI 0.03% (after the close)
Travere Therapeutics, Inc. TVTX 0.36% (after the close)
NovaBay Pharmaceuticals, Inc. NBY 3.22% (after the close)
Kura Oncology, Inc. KURA 2.04% (after the close)
Natera, Inc. NTRA 0.62% (after the close)
Zogenix ZGNX 0.84% (after the close)
Nektar Therapeutics NKTR 2.39% (after the close)
Eiger BioPharmaceuticals, Inc. EIGR 1.39% (after the close)
Vir Biotechnology, Inc. VIR 0.19% (after the close)
Iovance Biotherapeutics, Inc. IOVA 0.32% (after the close)
Evofem Biosciences, Inc. EVFM 1.37% (after the close)
Caladrius Biosciences, Inc. CLBS 0.62% (after the close)
Quidel Corporation QDEL 2.68% (after the close)
Corcept Therapeutics Incorporated CORT 2.86% (after the close)
Insulet Corporation PODD 2.1% (after the close)
Fluidigm Corporation FLDM 0.4% (after the close)
Cardiovascular Systems, Inc. CSII 0.88% (after the close)
CytomX Therapeutics, Inc. CTMX 1.37% (after the close)
Cytokinetics, Incorporated CYTK 3.6% (after the close)
Dynavax Technologies Corporation DVAX 4.59% (after the close)
Collegium Pharmaceutical, Inc. COLL 0.22% (after the close)
Enanta Pharmaceuticals, Inc. ENTA 1.19% (after the close)
Fulgent Genetics, Inc. FLGT 3.23% (after the close)
Chembio Diagnostics, Inc. CEMI 2.44% (after the close)
Guardant Health, Inc. GH 1.07% (after the close)
Tricida, Inc. TCDA 3.93% (after the close)
Neovasc Inc. NVCN 0.13% (after the close)
Spero Therapeutics, Inc. SPRO 0.51% (after the close)
Misonix, Inc. MSON 2.01% (after the close)

Friday

Elanco Animal Health Incorporated ELAN 1.34% (before the market open)
Amneal Pharmaceuticals, Inc. AMRX 2.73% (before the market open)
ANI Pharmaceuticals, Inc. ANIP 0.21% (before the market open)
Avanos Medical, Inc. AVNS 1.73% (before the market open)
Meridian Bioscience, Inc. VIVO 2.05% (before the market open)
Radius Health, Inc. RDUS 0.54% (before the market open)

IPOs

IPO Pricing

Valneva SE, a French company focused on prophylactic vaccines for infectious diseases, intends to offer 7.083 million of its ordinary shares. The offering will comprise an initial public offering of ADSs, each representing two ordinary shares, in the U.S., and a concurrent private placement of ordinary shares in certain jurisdictions outside of the U.S.

The company has applied to list its ADSs on the Nasdaq under the ticker symbol VALN. The ADS offering is expected to be priced at $28.24 per ADS, based on the last reported sale price of its ordinary shares on Euronext Paris on April 27.

Lakeway, Texas-based Anebulo Pharmaceuticals, Inc. is proposing to offer 3 million shares of its common stock in an IPO, with the price estimated in the range of $6-$8. The clinical-stage biotechnology company is working on products for people suffering from cannabinoid overdose and substance addiction. It has applied for listing its shares on the Nasdaq under the ticker symbol ANEB.

IPO Quiet Period Expiry

VectivBio Holding AG VECT 4.13%
Reneo Pharmaceuticals, Inc. (NASDAQ: RPHM)

https://www.benzinga.com/general/biotech/21/05/20903835/week-ahead-in-biotech-may-2-8-chemocentryx-adcom-ophthalmology-conference-presentations-earnings-

Sarepta to Update May 3 on Next-Gen Investigational Duchenne Treatment

  Sarepta Therapeutics, Inc. (NASDAQ:SRPT), the leader in precision genetic medicine for rare diseases, today announced that on Monday, May 3, 2021 at 8:30 am Eastern Time, the Company will host a webcast and conference call to present results from the 30 mg/kg arm of the MOMENTUM study, a multiple-ascending dose clinical trial of SRP-5051 for the treatment of Duchenne muscular dystrophy. SRP-5051 is the first investigational treatment using Sarepta’s next-generation PPMO platform, which is designed around a proprietary cell-penetrating peptide conjugated to Sarepta’s phosphorodiamidate morpholino oligomer (PMO) backbone with the goal of increasing drug concentration in muscle tissue.

The presentation will be webcast live under the investor relations section of Sarepta's website at https://investorrelations.sarepta.com/events-presentations and slides will be archived there following the call for one year. Please connect to Sarepta's website several minutes prior to the start of the broadcast to ensure adequate time for any software download that may be necessary. The conference call may be accessed by dialing (844) 534-7313 for domestic callers and (574) 990-1451 for international callers. The passcode for the call is 1016246. Please specify to the operator that you would like to join the “Sarepta-hosted Clinical Update for MOMENTUM call.”

https://www.biospace.com/article/releases/sarepta-therapeutics-to-share-clinical-update-for-30-mg-kg-arm-of-momentum-study-for-srp-5051-its-investigational-ppmo-for-the-treatment-of-duchenne-muscular-dystrophy/

FDA Approves Higher Dosage of Naloxone Nasal Spray to Treat Opioid Overdose

 The U.S. Food and Drug Administration announced today the approval of a higher dose naloxone hydrochloride nasal spray product to treat opioid overdose. The newly approved product delivers 8 milligrams (mg) of naloxone into the nasal cavity. The FDA had previously approved 2 mg and 4 mg naloxone nasal spray products.

Naloxone is a medicine that can be administered by individuals with or without medical training to help reduce opioid overdose deaths. If naloxone is administered quickly, it can counter the opioid overdose effects, usually within minutes. A higher dose of naloxone provides an additional option in the treatment of opioid overdoses.  

"Today's action meets another critical need in combatting opioid overdose," said Patrizia Cavazzoni, M.D., director of the FDA's Center for Drug Evaluation and Research. "Addressing the opioid crisis is a top priority for the FDA, and we will continue our efforts to increase access to naloxone and place this important medicine in the hands of those who need it most."

Over the last several years, the FDA has taken a number of steps to improve availability of naloxone products, including: encouraging manufacturers to pursue approval of over-the-counter naloxone products; requiring drug manufacturers for all opioid pain relievers and medicines to treat opioid use disorder to add new recommendations about naloxone to the prescribing information; and extending the shelf life of naloxone nasal spray from 24 months to 36 months.

The FDA is committed to using its regulatory authority to address the opioid crisis with a focus on: decreasing exposure to opioids and preventing new addiction; fostering the development of novel pain treatment therapies; supporting treatment of those with opioid use disorder; and improving enforcement and assessing benefit-risk.

The use of naloxone in patients who are opioid-dependent may result in opioid withdrawal characterized by body aches, diarrhea, increased heart rate (tachycardia), fever, runny nose, sneezing, goose bumps (piloerection), sweating, yawning, nausea or vomiting, nervousness, restlessness or irritability, shivering or trembling, abdominal cramps, weakness and increased blood pressure.

The FDA granted approval of KLOXXADO to Hikma Pharmaceuticals through the 505(b)(2) approval pathway under the Federal Food, Drug, and Cosmetic Act. A new drug application submitted through this pathway may rely on the FDA's finding that a previously approved drug is safe and effective or on published literature to support the safety and/or effectiveness of the proposed product, if such reliance is scientifically justified. In this case, the manufacturer submitted a 505(b)(2) application that relied, in part, on the FDA's finding of safety and effectiveness for naloxone hydrochloride (NARCAN injection) to support approval. The applicant demonstrated that reliance on the FDA's finding of safety and effectiveness for Narcan was scientifically justified and provided KLOXXADO-specific pharmacokinetic data to establish the drug's safety and efficacy for its approved use.

https://www.biospace.com/article/releases/fda-approves-higher-dosage-of-naloxone-nasal-spray-to-treat-opioid-overdose/

Chip for faster genome sequencing tests developed

 Jeremy Edwards, director of the Computational Genomics and Technology (CGaT) Laboratory at The University of New Mexico, and his colleagues at Centrillion Technologies in Palo Alto, Calif. and West Virginia University, have developed a chip that provides a simpler and more rapid method of genome sequencing for viruses like COVID-19.

Their research, titled, "Highly Accurate Chip-Based Resequencing of SARS-CoV-2 Clinical Samples" was published recently in the American Chemical Society's Langmuir. As part of the research, scientists created a tiled genome array they developed for rapid and inexpensive full viral genome resequencing and applied their SARS-CoV-2-specific genome tiling array to rapidly and accurately resequenced the viral genome from eight clinical samples acquired from patients in Wyoming that tested positive for SARS-CoV-2. Ultimately, they were able to sequence 95 percent of the genome of each sample with greater than 99.9 percent accuracy.

"This new technology allows for faster and more accurate tracing of COVID and other respiratory viruses, including the appearance of new variants," said Edwards, who is a professor in the UNM Department of Chemistry and Chemical Biology. "With this simple and rapid testing procedure, scientists will be able to more accurately track the progression and better prevent the onset of the next pandemic."

With more than 142 million people worldwide having contracted the virus, vigilant testing and contact tracing are the most effective ways to slow the spread of COVID-19. Traditional methods of clinical testing often produce false positives or negatives, and traditional methods of sequencing are time-consuming and expensive. This new technology will virtually eliminate all of these barriers.

"Since the submission of the paper, the technology has further evolved with improved accuracy and sensitivity," said Edwards. "The chip technology is the best available technology for large-scale viral genome surveillance and monitoring viral variants. This technology could not only help control this pandemic and also prevent future pandemics."

The mission of the Computational Genomics and Technology (CGaT) Laboratory is to provide training in bioinformatics research for undergraduate, master's and Ph.D. students, as well as postdoctoral fellows; provide collaborative research interactions to utilize bioinformatics computing tools for researchers at UNM, and to conduct state-of-the-art and innovative bioinformatics and genomics research within the center.

https://www.eurekalert.org/pub_releases/2021-04/uonm-rdc042921.php

Move over CRISPR, the Retrons are coming

 Researchers have created a new gene editing tool called Retron Library Recombineering (RLR) that can generate up to millions of mutations simultaneously, and 'barcodes' mutant bacterial cells so that the entire pool can be screened at once. It can be used in contexts where CRISPR is toxic or not feasible, and results in better editing rates.

While the CRISPR-Cas9 gene editing system has become the poster child for innovation in synthetic biology, it has some major limitations. CRISPR-Cas9 can be programmed to find and cut specific pieces of DNA, but editing the DNA to create desired mutations requires tricking the cell into using a new piece of DNA to repair the break. This bait-and-switch can be complicated to orchestrate, and can even be toxic to cells because Cas9 often cuts unintended, off-target sites as well.

Alternative gene editing techniques called recombineering instead perform this bait-and-switch by introducing an alternate piece of DNA while a cell is replicating its genome, efficiently creating genetic mutations without breaking DNA. These methods are simple enough that they can be used in many cells at once to create complex pools of mutations for researchers to study. Figuring out what the effects of those mutations are, however, requires that each mutant be isolated, sequenced, and characterized: a time-consuming and impractical task.

Researchers at the Wyss Institute for Biologically Inspired Engineering at Harvard University and Harvard Medical School (HMS) have created a new gene editing tool called Retron Library Recombineering (RLR) that makes this task easier. RLR generates up to millions of mutations simultaneously, and "barcodes" mutant cells so that the entire pool can be screened at once, enabling massive amounts of data to be easily generated and analyzed. The achievement, which has been accomplished in bacterial cells, is described in a recent paper in PNAS.

"RLR enabled us to do something that's impossible to do with CRISPR: we randomly chopped up a bacterial genome, turned those genetic fragments into single-stranded DNA in situ, and used them to screen millions of sequences simultaneously," said co-first author Max Schubert, Ph.D., a postdoc in the lab of Wyss Core Faculty member George Church, Ph.D. "RLR is a simpler, more flexible gene editing tool that can be used for highly multiplexed experiments, which eliminates the toxicity often observed with CRISPR and improves researchers' ability to explore mutations at the genome level."

Retrons: from enigma to engineering tool

Retrons are segments of bacterial DNA that undergo reverse transcription to produce fragments of single-stranded DNA (ssDNA). Retrons' existence has been known for decades, but the function of the ssDNA they produce flummoxed scientists from the 1980s until June 2020, when a team finally figured out that retron ssDNA detects whether a virus has infected the cell, forming part of the bacterial immune system.

While retrons were originally seen as simply a mysterious quirk of bacteria, researchers have become more interested in them over the last few years because they, like CRISPR, could be used for precise and flexible gene editing in bacteria, yeast, and even human cells.

"For a long time, CRISPR was just considered a weird thing that bacteria did, and figuring out how to harness it for genome engineering changed the world. Retrons are another bacterial innovation that might also provide some important advances," said Schubert. His interest in retrons was piqued several years ago because of their ability to produce ssDNA in bacteria -- an attractive feature for use in a gene editing process called oligonucleotide recombineering.

Recombination-based gene editing techniques require integrating ssDNA containing a desired mutation into an organism's DNA, which can be done in one of two ways. Double-stranded DNA can be physically cut (with CRISPR-Cas9, for example) to induce the cell to incorporate the mutant sequence into its genome during the repair process, or the mutant DNA strand and a single-stranded annealing protein (SSAP) can be introduced into a cell that is replicating so that the SSAP incorporates the mutant strand into the daughter cells' DNA.

"We figured that retrons should give us the ability to produce ssDNA within the cells we want to edit rather than trying to force them into the cell from the outside, and without damaging the native DNA, which were both very compelling qualities," said co-first author Daniel Goodman, Ph.D., a former Graduate Research Fellow at the Wyss Institute who is now a Jane Coffin Childs Postdoctoral Fellow at UCSF.

Another attraction of retrons is that their sequences themselves can serve as "barcodes" that identify which individuals within a pool of bacteria have received each retron sequence, enabling dramatically faster, pooled screens of precisely-created mutant strains.

To see if they could actually use retrons to achieve efficient recombineering with retrons, Schubert and his colleagues first created circular plasmids of bacterial DNA that contained antibiotic resistance genes placed within retron sequences, as well as an SSAP gene to enable integration of the retron sequence into the bacterial genome. They inserted these retron plasmids into E. coli bacteria to see if the genes were successfully integrated into their genomes after 20 generations of cell replication. Initially, less than 0.1% of E. coli bearing the retron recombineering system incorporated the desired mutation.

To improve this disappointing initial performance, the team made several genetic tweaks to the bacteria. First, they inactivated the cells' natural mismatch repair machinery, which corrects DNA replication errors and could therefore be "fixing" the desired mutations before they were able to be passed on to the next generation. They also inactivated two bacterial genes that code for exonucleases -- enzymes that destroy free-floating ssDNA. These changes dramatically increased the proportion of bacteria that incorporated the retron sequence, to more than 90% of the population.

Name tags for mutants

Now that they were confident that their retron ssDNA was incorporated into their bacteria's genomes, the team tested whether they could use the retrons as a genetic sequencing "shortcut," enabling many experiments to be performed in a mixture. Because each plasmid had its own unique retron sequence that can function as a "name tag," they reasoned that they should be able to sequence the much shorter retron rather than the whole bacterial genome to determine which mutation the cells had received.

First, the team tested whether RLR could detect known antibiotic resistance mutations in E coli. They found that it could -- retron sequences containing these mutations were present in much greater proportions in their sequencing data compared with other mutations. The team also determined that RLR was sensitive and precise enough to measure small differences in resistance that result from very similar mutations. Crucially, gathering these data by sequencing barcodes from the entire pool of bacteria rather than isolating and sequencing individual mutants, dramatically speeds up the process.

Then, the researchers took RLR one step further to see if it could be used on randomly-fragmented DNA, and find out how many retrons they could use at once. They chopped up the genome of a strain of E. coli highly resistant to another antibiotic, and used those fragments to build a library of tens of millions of genetic sequences contained within retron sequences in plasmids. "The simplicity of RLR really shone in this experiment, because it allowed us to build a much bigger library than what we can currently use with CRISPR, in which we have to synthesize both a guide and a donor DNA sequence to induce each mutation," said Schubert.

This library was then introduced into the RLR-optimized E coli strain for analysis. Once again, the researchers found that retrons conferring antibiotic resistance could be easily identified by the fact that they were enriched relative to others when the pool of bacteria was sequenced.

"Being able to analyze pooled, barcoded mutant libraries with RLR enables millions of experiments to be performed simultaneously, allowing us to observe the effects of mutations across the genome, as well as how those mutations might interact with each other," said senior author George Church, who leads the Wyss Institute's Synthetic Biology Focus Area and is also a Professor of Genetics at HMS. "This work helps establish a road map toward using RLR in other genetic systems, which opens up many exciting possibilities for future genetic research."

Another feature that distinguishes RLR from CRISPR is that the proportion of bacteria that successfully integrate a desired mutation into their genome increases over time as the bacteria replicate, whereas CRISPR's "one shot" method tends to either succeed or fail on the first try. RLR could potentially be combined with CRISPR to improve its editing performance, or could be used as an alternative in the many systems in which CRISPR is toxic.

More work remains to be done on RLR to improve and standardize editing rate, but excitement is growing about this new tool. RLR's simple, streamlined nature could enable the study of how multiple mutations interact with each other, and the generation of a large number of data points that could enable the use of machine learning to predict further mutational effects.

"This new synthetic biology tool brings genome engineering to an even higher levels of throughput, which will undoubtedly lead to new, exciting, and unexpected innovations," said Don Ingber, M.D., Ph.D., the Wyss Institute's Founding Director. Ingber is also the Judah Folkman Professor of Vascular Biology at HMS and Boston Children's Hospital, and Professor of Bioengineering at the Harvard John A. Paulson School of Engineering and Applied Sciences.

Additional authors of the paper include Timothy Wannier from HMS, Divjot Kaur from the University of Warwick, Fahim Farzadfard and Timothy Lu from the Massachusetts Institute of Technology, and Seth Shipman from the Gladstone Institute of Data Science and Biotechnology.

This research was supported by the United States Department of Energy (DE-FG02-02ER63445) and by the National Defense Science and Engineering Graduate Fellowship.

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Story Source:

Materials provided by Wyss Institute for Biologically Inspired Engineering at Harvard. Original written by Lindsay Brownell. Note: Content may be edited for style and length.

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Journal Reference:

1. Max G. Schubert, Daniel B. Goodman, Timothy M. Wannier, Divjot Kaur, Fahim Farzadfard, Timothy K. Lu, Seth L. Shipman, George M. Church. High-throughput functional variant screens via in vivo production of single-stranded DNA. Proceedings of the National Academy of Sciences, 2021; 118 (18): e2018181118 DOI: 10.1073/pnas.2018181118

https://www.sciencedaily.com/releases/2021/04/210430120411.htm

Access to mental health services dwindled as pandemic need strained providers: GAO

 Access to mental health services dwindled as providers were strained and under the demand for care during the COVID-19 pandemic, according to a Government Accountability Office (GAO) report made public on Friday. 

The GAO concluded that the number of people experiencing anxiety, depression and drug overdoses heightened during the pandemic, while mental health professionals dealt with layoffs, decreased hours and having to turn away patients. 

Respondents to Centers for Disease Control and Prevention (CDC) surveys determined that about 38 percent reported symptoms of anxiety or depression between April 2020 and February 2021. Eleven percent said the same in 2019. 

Similarly, emergency departments saw 36 percent more visits for overdoses and 26 percent more visits for suicide attempts from mid-March to mid-October of last year, compared to the previous year. 

At the same time, the National Council for Behavioral Health (NCBH) surveyed its members in February 2021 and found that in the three months before the survey, about two-thirds of member organizations saw an escalation in demand, leading them to have to cancel or reschedule appointments or turn patients away.  

The report also cited federal data that showed that there were not enough mental health professionals available, and this contributed to the lack of access, particularly in rural areas.

The NCBH survey found 45 percent of member organizations closed some programs, 35 percent reduced staff hours, 27 percent laid off employees and 23 percent furloughed employees. 

The GAO said other factors contributing to the lack of access included provider reimbursement rates and health system capacity, citing interviews of stakeholders including officials from NCBH and hospital associations and insurance regulators in Oregon, Pennsylvania, Texas and Virginia. 

Most provider groups interviewed reported more issues with payment through Medicaid than other payers, according to the report. 

The office said there was not currently data showing insurers violated mental health parity law, although interviewees presented anecdotal examples. The law prevents companies from charging patients more for mental health care than they would for medical or surgical care.

Kaiser Health News first reported on the GAO report. 

Senate Finance Committee Chairman Ron Wyden (D-Ore.) had requested in May 2020 that the GAO research mental health access and the pandemic’s effects on mental health, a request that resulted in this report. 

“Underlying the global pandemic is a five-alarm fire when it comes to the state of Americans’ mental health,” Wyden said in a statement. “The pandemic has made access to mental health care more urgent than ever while worsening long-standing shortcomings in the system.”

“Mental health and physical health ought to be on the same footing in America’s health care system, and I will be using my position as Chairman of the Finance Committee to make that a reality,” he added.

https://thehill.com/policy/healthcare/551260-access-to-mental-health-services-dwindled-amid-increasing-demand-during

Cities, states experiment with vax incentives

 States and cities are experimenting with offering incentives and privileges for residents to get vaccinated for COVID-19 as concerns have mounted over the slowdown in vaccinations across the U.S. 

Officials are turning to initiatives such as giving vaccine recipients payments through savings bonds, free drinks or gift cards to motivate Americans to get their COVID-19 shot. Public health and psychology experts said these programs have the potential to bring in more people willing to get the vaccine and that incentives are worth a try to close the country’s gap in vaccinations.

This week, West Virginia committed to giving those aged 16 to 35 who get the vaccine $100 in savings bonds to boost the state’s vaccination numbers. Gov. Jim Justice (R) reported on Monday that 52 percent of the eligible state population has received at least one dose and noted the cost would be “so minuscule” compared with what the state has spent and keeps spending on the pandemic.

Connecticut plans to take a different approach in launching its #CTDrinksOnUs campaign, through which vaccine recipients will be eligible for one free drink with the purchase of food between May 19 and 31 at participating locations.  

Max Reiss, the director of communications for Connecticut Gov. Ned Lamont (D), said the state’s drink program arose as officials and the restaurant industry brainstormed how to reach “herd immunity” — a point at which most of the population is immune to the virus.  

The idea for the program was not “directly linked” to the slowdown of vaccinations seen in the state and nationally, Reiss said.

When asked if the drink incentive had the ability to get the state to a herd immunity point, he responded, “We don’t think it hurts.”

“If there's an extra bonus that when you go to the restaurant, you can get a drink or a beer or a glass of wine or a soda, we think that's a nice token that you can enjoy,” he said. “And it shows that if you're vaccinated, you can do all these things safely.”

City and county governments are also exploring incentive approaches to increase vaccinations, with Chicago working on two programs in which fully vaccinated people would have special access to summer events and special offers for salon and barbershop services. On Wednesday, Harris County in Texas approved up to $250,000 to be used for gift cards, events and other incentives for vaccinated people, the Houston Chronicle reported. 

Starting on Monday, Detroit is offering $50 prepaid debit cards to anyone who drives another person to get their vaccination, as long as they preregister. Deputy Mayor Conrad Mallett said officials hope, through the program, that trusted voices within communities will be inspired to help other members decide to get the COVID-19 shot and therefore raise Detroit’s vaccination numbers.  

“Pushing past our inability to manage and win the argument on social media, we really had to be more inventive about how to get the attention of the greater, grander community,” he said. 

Detroit officials decided on giving the incentive to those who give their “time and effort” to help others get vaccinated instead of paying directly due to concerns about the “ethics of that.”

“Getting vaccinated is an important decision,” Mallett said. “And we didn't want to try to muddy up that decisionmaking process by trying to encourage people to do what we think is right but pay them to do it.”

The push for incentives comes as the average number of vaccines administered daily in the U.S. has been declining in recent days, which experts have attributed to a waning demand for vaccines after enthusiastic recipients have already gotten their shots.

The U.S. hit a peak in its seven-day average of daily vaccinations on April 13 with 3.38 million, but that number has since fallen to 2.63 million as of Thursday, according to Our World in Data. 

Overall, the Centers for Disease Control and Prevention reports that 55.4 percent of American adults have received at least one dose, and 39 percent are considered fully vaccinated, meaning much of the population is still particularly susceptible to contracting the virus. 

William Schaffner, a professor of infectious diseases and preventive medicine at Vanderbilt University Medical Center, said vaccinating more of the country’s population is important because it will “substantially diminish” COVID-19’s spread and the impact of variants. 

“Anything we can do to provide incentives to get more of those people vaccinated I think is a good thing,” he said. “Whether these incentives work, we'll have to wait and see. I'm sure they'll work with some people. There's no doubt about that, but whether they can really help us turn the tide remains to be seen.”

These state and local governments are taking a page out of some businesses’ playbooks, including Krispy Kreme, which offers a free doughnut every day of 2021 to Americans who prove they got their shot. 

Experts said research shows that incentives can be effective at influencing health behaviors, with Noel Brewer, a professor of health behavior at the University of North Carolina, saying incentives are expected to increase vaccinations by about 8 percent. 

“This idea of letting people choose and empowering freedom of choice could be quite appealing to people on the right and on the left, so this seems like a palatable approach,” Brewer said. 

This week in Michigan, Gov. Gretchen Whitmer (D) also unveiled a reopening plan that connects loosening COVID-19 restrictions to increased vaccination rates. Under the plan, once the state documents that 70 percent of the eligible population received at least one dose, its orders on masks and limitations for public and private gatherings would be dropped. 

Brewer said incentives are stronger when there’s “a clear contingency between an individual’s behavior and the reward,” so Michigan should expect to see “a weaker effect or maybe no effect” when compared to a direct incentive. 

Austin Baldwin, an associate professor of psychology at Southern Methodist University, said in general mandates can be “very effective,” but when it comes to vaccinations, those who are resistant or hesitant may not respond well to vaccine requirements if they're perceived as “threatening.”

“At least in the current context, incentives might be sort of a more effective approach because incentives at least sort of still value, at a psychological level, that autonomy, and people can feel like they're making that decision on their own accord,” Baldwin said.

https://thehill.com/policy/healthcare/551246-cities-states-experiment-with-incentives-for-vaccinations