7Baggers

TELA Bio, Inc
(NASDAQ:TELA) 

TELA stock logo

TELA Bio, Inc., a medical technology company, focuses on the design, development, and marketing of tissue reinforcement materials to address unmet needs in soft tissue reconstruction. The company provides a portfolio of OviTex Reinforced Tissue Matrix (OviTex) products for hernia repair and abdomina...

Founded: 2012
IPO Price: $13 (Nov 08, 2019)
Full Time Employees: 89
CEO: Antony Koblish  
Sector: Healthcare
Industry: Medical Devices

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At a glance:
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Quarterly
Annual
    Unit: USD2026-03-31 2025-12-31 2025-09-30 2025-06-30 2025-03-31 2024-12-31 2024-09-30 2024-06-30 2024-03-31 2023-12-31 2023-09-30 2023-06-30 2023-03-31 2022-12-31 2022-09-30 2022-06-30 2022-03-31 2021-12-31 2021-09-30 2021-06-30 2021-03-31 2020-12-31 2020-09-30 2020-06-30 2020-03-31 2019-12-31 2019-09-30 
                               
      revenue
    19,059,000 20,869,000 20,689,000 20,197,000 18,520,000 17,649,000 18,957,000 16,091,000 16,603,000 16,998,000 15,052,000 14,494,000 11,909,000 11,622,000 11,159,000 10,406,000 8,231,000 8,374,000 7,654,000 7,558,000 5,877,000 5,667,000 5,313,000 3,507,000 3,726,000 4,864,000 3,973,000 
      yoy
    2.91% 18.24% 9.14% 25.52% 11.55% 3.83% 25.94% 11.02% 39.42% 46.26% 34.89% 39.29% 44.68% 38.79% 45.79% 37.68% 40.05% 47.77% 44.06% 115.51% 57.73% 16.51% 33.73%     
      qoq
    -8.67% 0.87% 2.44% 9.06% 4.94% -6.90% 17.81% -3.08% -2.32% 12.93% 3.85% 21.71% 2.47% 4.15% 7.24% 26.42% -1.71% 9.41% 1.27% 28.60% 3.71% 6.66% 51.50% -5.88% -23.40% 22.43%  
      cost of revenue
    6,444,000 7,019,000 6,625,000 5,997,000 5,913,000 6,333,000 6,004,000 4,923,000 5,172,000 5,279,000 4,568,000 4,198,000 3,916,000 3,351,000 3,745,000 3,318,000 3,156,000 2,639,000 2,976,000 2,395,000 2,336,000 1,929,000 1,950,000 1,346,000 1,450,000 1,825,000 1,293,000 
      amortization of intangible assets
    95,000 95,000 95,000 95,000 95,000 95,000 95,000 95,000 95,000 95,000 95,000 95,000 95,000 95,000 95,000 538,000 76,000 76,000 76,000 76,000 76,000 76,000 76,000 76,000 76,000 76,000 76,000 
      gross profit
    12,520,000 13,755,000 13,969,000 14,105,000 12,512,000 11,221,000 12,858,000 11,073,000 11,336,000 11,624,000 10,389,000 10,201,000 7,898,000 8,176,000 7,319,000 6,550,000 4,999,000 5,659,000 4,602,000 5,087,000 3,465,000 3,662,000 3,287,000 2,085,000 2,200,000 2,963,000 2,604,000 
      yoy
    0.06% 22.58% 8.64% 27.38% 10.37% -3.47% 23.77% 8.55% 43.53% 42.17% 41.95% 55.74% 57.99% 44.48% 59.04% 28.76% 44.27% 54.53% 40.01% 143.98% 57.50% 23.59% 26.23%     
      qoq
    -8.98% -1.53% -0.96% 12.73% 11.51% -12.73% 16.12% -2.32% -2.48% 11.89% 1.84% 29.16% -3.40% 11.71% 11.74% 31.03% -11.66% 22.97% -9.53% 46.81% -5.38% 11.41% 57.65% -5.23% -25.75% 13.79%  
      gross margin %
    65.69% 65.91% 67.52% 69.84% 67.56% 63.58% 67.83% 68.81% 68.28% 68.38% 69.02% 70.38% 66.32% 70.35% 65.59% 62.94% 60.73% 67.58% 60.13% 67.31% 58.96% 64.62% 61.87% 59.45% 59.04% 60.92% 65.54% 
      operating expenses:
                               
      sales and marketing
    16,537,000 14,490,000 15,227,000 16,857,000 16,608,000 13,957,000 16,472,000 16,699,000 17,520,000 17,164,000 14,474,000 14,577,000 13,466,000 11,647,000 11,172,000 11,055,000 9,378,000 8,313,000 6,948,000 7,502,000 6,299,000 6,377,000 6,342,000 4,123,000 5,269,000 5,382,000 4,736,000 
      general and administrative
    4,166,000 3,784,000 3,948,000 4,126,000 3,836,000 3,589,000 3,683,000 3,621,000 3,829,000 4,053,000 3,728,000 3,472,000 3,634,000 3,242,000 3,532,000 3,630,000 3,458,000 3,275,000 3,462,000 2,966,000 2,756,000 2,869,000 2,607,000 2,149,000 2,518,000 2,486,000 1,208,000 
      research and development
    2,343,000 2,129,000 2,348,000 2,203,000 2,540,000 2,029,000 2,068,000 2,323,000 2,393,000 2,685,000 2,368,000 2,514,000 2,052,000 2,726,000 2,102,000 2,102,000 2,007,000 1,725,000 1,409,000 1,930,000 1,679,000 1,163,000 1,201,000 979,000 912,000 921,000 516,000 
      total operating expenses
    23,046,000 20,403,000 21,523,000 23,186,000 22,984,000 19,575,000 22,223,000 22,643,000 23,742,000 23,902,000 20,570,000 20,563,000 19,152,000 17,615,000 16,806,000 16,787,000 14,843,000 13,313,000 11,819,000 12,398,000 10,734,000 10,409,000 10,150,000 7,251,000 8,699,000 8,789,000 6,460,000 
      income from operations
    -10,526,000 -6,648,000 -7,554,000 -9,081,000 -10,472,000 -8,354,000 -9,365,000 -11,570,000 -4,826,000 -12,278,000 -10,181,000 -10,362,000 -11,254,000 -9,439,000 -9,487,000 -10,237,000 -9,844,000 -7,654,000 -7,217,000 -7,311,000 -7,269,000 -6,747,000 -6,863,000 -5,166,000 -6,499,000 -5,826,000 -3,856,000 
      yoy
    0.52% -20.42% -19.34% -21.51% 116.99% -31.96% -8.01% 11.66% -57.12% 30.08% 7.32% 1.22% 14.32% 23.32% 31.45% 40.02% 35.42% 13.44% 5.16% 41.52% 11.85% 15.81% 77.98%     
      qoq
    58.33% -11.99% -16.82% -13.28% 25.35% -10.80% -19.06% 139.74% -60.69% 20.60% -1.75% -7.93% 19.23% -0.51% -7.33% 3.99% 28.61% 6.06% -1.29% 0.58% 7.74% -1.69% 32.85% -20.51% 11.55% 51.09%  
      operating margin %
    -55.23% -31.86% -36.51% -44.96% -56.54% -47.33% -49.40% -71.90% -29.07% -72.23% -67.64% -71.49% -94.50% -81.22% -85.02% -98.38% -119.60% -91.40% -94.29% -96.73% -123.69% -119.06% -129.17% -147.31% -174.42% -119.78% -97.06% 
      other income:
                               
      interest expense
    -2,053,000 -1,637,000 -1,201,000 -1,188,000 -1,219,000 -1,283,000 -1,344,000 -1,331,000 -1,332,000 -1,345,000 -1,334,000 -1,298,000 -1,246,000 -1,174,000 -1,032,000 -934,000 -911,000 -922,000 -922,000 -864,000 -889,000 -903,000 -898,000 -884,000 -879,000 -884,000 -899,000 
      other income
    366,000 277,000 152,000 379,000 479,000 285,000 337,000 301,000 497,000 733,000 558,000 870,000 473,000    -107,000 -43,000 -127,000 -80,000 22,000 -140,000 58,000 -31,000 158,000 179,000 55,000 
      total other expense
    -1,687,000 -2,248,000 -1,049,000 -809,000 -740,000 -998,000 -1,007,000 -1,030,000 -835,000 -612,000 -776,000 -428,000 -773,000 -540,000 -1,227,000 -2,504,000 -1,018,000 -965,000 -1,049,000 -944,000 -867,000       
      loss before income tax expense
    -12,213,000 -7,426,250 -8,603,000 -9,890,000 -11,212,000                       
      income tax expense
    -60,000 -21,250  -33,000 -52,000                       
      net income
    -12,273,000 -9,041,000 -8,603,000 -9,923,000 -11,264,000 -9,208,000 -10,372,000 -12,600,000 -5,661,000 -12,890,000 -10,957,000 -10,790,000 -12,027,000 -9,979,000 -10,714,000 -12,741,000 -10,862,000 -8,619,000 -8,266,000 -8,255,000 -8,136,000 -7,790,000 -7,703,000 -6,081,000 -7,220,000 -6,532,000 -4,666,000 
      yoy
    8.96% -1.81% -17.06% -21.25% 98.98% -28.56% -5.34% 16.77% -52.93% 29.17% 2.27% -15.31% 10.73% 15.78% 29.62% 54.34% 33.51% 10.64% 7.31% 35.75% 12.69% 19.26% 65.09%     
      qoq
    35.75% 5.09% -13.30% -11.91% 22.33% -11.22% -17.68% 122.58% -56.08% 17.64% 1.55% -10.29% 20.52% -6.86% -15.91% 17.30% 26.02% 4.27% 0.13% 1.46% 4.44% 1.13% 26.67% -15.78% 10.53% 39.99%  
      net income margin %
    -64.39% -43.32% -41.58% -49.13% -60.82% -52.17% -54.71% -78.30% -34.10% -75.83% -72.79% -74.44% -100.99% -85.86% -96.01% -122.44% -131.96% -102.93% -108.00% -109.22% -138.44% -137.46% -144.98% -173.40% -193.77% -134.29% -117.44% 
      net loss per common share, basic and diluted
    -210 -170 -190 -220 -250 -170 -420 -510 -230 -530 -450 -460 -630 -480 -640 -880 -750 -590 -570 -570 -560 -540 -530 -530 -630 59,520 -22,580 
      weighted-average common shares outstanding, basic and diluted
    57,256,518,000 46,947,932,000 45,421,795,000 45,365,325,000 45,267,020,000 28,526,441,000 24,703,578,000 24,663,234,000 24,579,386,000 22,868,663,000 24,483,664,000 23,239,262,000 19,185,621,000 16,267,678,000 16,758,573,000 14,557,453,000 14,538,864,000 14,473,213,000 14,485,688,000 14,458,911,000 14,438,405,000 12,934,421,000 14,421,990,000 11,443,122,000 11,406,783,000 1,766,412,000 297,750,000 
      comprehensive loss:
                               
      foreign currency translation adjustment
    -6,000  -2,000 2,000 1,000 -59,000 51,000 1,000 6,000 -44,000 51,000 -36,000 -30,000 -112,000 133,000 134,000 47,000 -9,000 38,000 1,000 -11,000 -54,000 -29,000 4,000 27,000  1,000 
      comprehensive loss
    -12,279,000 -9,041,000 -8,605,000 -9,921,000 -11,263,000 -9,267,000 -10,321,000 -12,599,000 -5,655,000 -12,934,000 -10,906,000 -10,826,000 -12,057,000 -10,091,000 -10,581,000 -12,607,000 -10,815,000 -8,628,000 -8,228,000 -8,254,000 -8,147,000 -7,844,000 -7,732,000 -6,077,000 -7,193,000 -6,549,000 -4,665,000 
      other operating income:
                               
      gain on sale of product line
            -7,580,000                   
      other expense:
                               
      loss on extinguishment of debt
                   -1,228,000            
      other expense
                 -161,000 -195,000 -342,000            
      change in fair value of preferred stock warrant liability
                              34,000 
      total other income
                         -619,000 -840,000 -915,000 -721,000 -706,000 -810,000 
      accretion of redeemable convertible preferred stock to redemption value
                             -940,000 -2,058,000 
      net loss attributable to common stockholders
                         -7,790,000 -7,703,000 -6,081,000 -7,220,000 -7,472,000 -6,724,000 
      gain on litigation settlement
                               
    Balance Sheets:
    Quarterly
    Annual
      Unit: USD2025-12-31 2025-09-30 2025-06-30 2025-03-31 2024-12-31 2024-09-30 2024-06-30 2024-03-31 2023-12-31 2023-09-30 2023-06-30 2023-03-31 2022-12-31 2022-09-30 2022-06-30 2022-03-31 2021-12-31 2021-09-30 2021-06-30 2021-03-31 2020-12-31 2020-09-30 2020-06-30 2020-03-31 2019-12-31 2019-09-30 
                                
        assets
                                
        current assets:
                                
        cash and cash equivalents
      50,845,000 29,713,000 34,977,000 42,833,000 52,670,000 17,301,000 26,496,000 37,143,000 46,729,000 58,202,000 65,266,000 30,124,000 42,019,000 54,226,000 27,725,000 33,016,000 43,931,000 53,636,000 60,292,000 65,829,000 74,394,000 81,467,000 85,471,000 41,411,000 45,302,000 10,701,000 
        accounts receivable
      10,347,000 11,274,000 11,236,000 10,557,000 10,098,000 11,222,000 9,097,000 9,955,000 9,737,000 8,072,000 7,894,000 6,654,000 6,621,000 5,688,000 5,306,000 4,311,000 4,234,000 3,573,000 3,545,000 2,795,000 2,683,000 2,640,000 2,586,000 2,047,000 2,836,000 2,278,000 
        inventory
      11,016,000 11,558,000 11,371,000 13,533,000 12,781,000 13,600,000 13,372,000 13,602,000 13,162,000 14,323,000 14,098,000 15,105,000 11,792,000 12,138,000 10,291,000 10,267,000 7,658,000 6,269,000 4,503,000 4,688,000 3,907,000 4,042,000 4,572,000 4,803,000 4,603,000 4,272,000 
        prepaid expenses and other current assets
      3,373,000 3,503,000 3,161,000 2,822,000 2,522,000 2,009,000                     
        total current assets
      75,581,000 56,048,000 60,745,000 69,745,000 78,071,000 44,132,000 51,109,000 62,618,000 71,726,000 82,252,000 89,168,000 53,502,000 62,447,000 73,955,000 45,634,000 50,329,000 59,055,000 65,539,000 70,735,000 75,204,000 83,225,000 89,016,000 94,113,000 55,313,000 64,334,000 17,616,000 
        property and equipment
      2,226,000 2,213,000 2,167,000 2,201,000 2,341,000 2,423,000 2,349,000 2,325,000 1,984,000 1,749,000 1,764,000 1,695,000 1,682,000 1,748,000 1,706,000 1,460,000 1,186,000 891,000 609,000 584,000 626,000 652,000 678,000 693,000 677,000 716,000 
        intangible assets
      1,359,000 1,454,000 1,549,000 1,644,000 1,739,000 1,834,000 1,929,000 2,024,000 2,119,000 2,214,000 2,309,000 2,404,000 2,499,000 2,594,000 2,689,000 2,227,000 2,303,000 2,379,000 2,455,000 2,531,000 2,607,000 2,683,000 2,759,000 2,835,000 2,911,000 2,987,000 
        right-of-use assets
      1,502,000 1,560,000 1,616,000 1,678,000 1,738,000 1,796,000 1,851,000 1,904,000 1,954,000 1,102,000 1,145,000 1,187,000 1,227,000 1,266,000 1,304,000            
        other long-term assets
      500,000  1,131,000 1,626,000 2,276,000 2,566,000 2,701,000 2,701,000                   
        deferred tax asset
       62,000 64,000 92,000 140,000                      
        restricted cash
      250,000 250,000 265,000 265,000 265,000 265,000 265,000 265,000 265,000                  
        total assets
      81,418,000 61,587,000 67,537,000 77,251,000 86,570,000 53,016,000 60,204,000 71,837,000 78,048,000 87,317,000 94,386,000 58,788,000 67,855,000 79,563,000 51,333,000 55,355,000 62,544,000 68,809,000 73,799,000 78,319,000 86,458,000 92,351,000 97,550,000 58,841,000 67,922,000 23,050,000 
        liabilities and stockholders’ equity
                                
        current liabilities:
                                
        accounts payable
      2,309,000 2,373,000 1,741,000 4,002,000 2,147,000 2,479,000 2,314,000 3,357,000 1,667,000 3,091,000 2,250,000 5,216,000 1,534,000 4,856,000 2,246,000 5,703,000 2,414,000 2,334,000 1,277,000 965,000 652,000 976,000 948,000 1,389,000 3,171,000 1,701,000 
        accrued expenses and other current liabilities
      15,666,000 14,604,000 13,987,000 12,534,000 13,451,000 14,379,000 12,675,000 11,822,000 15,300,000 12,243,000 10,795,000 9,190,000 10,869,000 10,358,000 9,680,000 6,583,000 8,161,000 7,043,000 6,017,000 4,673,000 5,953,000 4,369,000 2,675,000    
        total current liabilities
      17,975,000 16,977,000 19,061,000 16,536,000 15,598,000 16,858,000 14,989,000 15,179,000 16,967,000 15,334,000 13,045,000 14,406,000 12,403,000 15,214,000 11,926,000 12,286,000 10,575,000 9,377,000 7,294,000 5,638,000 6,605,000 5,345,000 3,623,000 4,232,000 6,713,000 6,309,000 
        long‑term debt
      55,653,000 41,494,000 38,051,000 41,275,000 41,124,000 40,970,000 40,817,000 40,665,000 40,515,000 40,363,000 40,212,000 40,063,000 39,916,000 39,766,000 39,617,000            
        other long‑term liabilities
      1,477,000 1,559,000 1,241,000 1,317,000 1,390,000 1,460,000 1,528,000 1,609,000 1,685,000 1,068,000 1,124,000 1,178,000 1,231,000 1,282,000 1,332,000 1,362,000 380,000 388,000 395,000 8,000    1,000 4,000 5,000 
        total liabilities
      75,105,000 60,030,000 58,353,000 59,128,000 58,112,000 59,288,000 57,334,000 57,453,000 59,167,000 56,765,000 54,381,000 55,647,000 53,550,000 56,262,000 52,875,000 45,317,000 42,446,000 41,080,000 38,834,000 36,628,000 37,432,000 36,018,000 34,147,000 34,614,000 36,960,000 38,066,000 
        commitments and contingencies
                                
        stockholders’ equity:
                                
        preferred stock; 0.001 par value: 10,000,000 shares authorized; no shares issued and outstanding
                                
        common stock; 0.001
      44,000 40,000 40,000 40,000 39,000 25,000 25,000 25,000 24,000 24,000 24,000 19,000 19,000 19,000 15,000 15,000 15,000 15,000 14,000 14,000 14,000 14,000 14,000 11,000 11,000  
        additional paid-in capital
      403,739,000 389,946,000 388,968,000 387,986,000 387,059,000 343,076,000 341,897,000 340,812,000 339,655,000 338,392,000 336,939,000 289,254,000 288,361,000 287,266,000 251,846,000 250,819,000 250,064,000 249,067,000 248,076,000 246,548,000 245,736,000 245,199,000 244,537,000 199,287,000 198,829,000  
        accumulated other comprehensive income
      91,000 91,000 93,000 91,000 90,000 149,000 98,000 97,000 91,000 135,000 84,000 120,000 150,000 262,000 129,000        12,000 8,000   
        accumulated deficit
      -397,561,000 -388,520,000 -379,917,000 -369,994,000 -358,730,000 -349,522,000 -339,150,000 -326,550,000 -320,889,000 -307,999,000 -297,042,000 -286,252,000 -274,225,000 -264,246,000 -253,532,000 -240,791,000 -229,929,000 -221,310,000 -213,044,000 -204,789,000 -196,653,000 -188,863,000 -181,160,000 -175,079,000 -167,859,000 -160,398,000 
        total stockholders’ equity
      6,313,000 1,557,000 9,184,000 18,123,000 28,458,000  2,870,000 14,384,000 18,881,000 30,552,000 40,005,000 3,141,000 14,305,000 23,301,000  10,038,000 20,098,000 27,729,000 34,965,000 41,691,000 49,026,000 56,333,000 63,403,000 24,227,000 30,962,000  
        total liabilities and stockholders’ equity
      81,418,000 61,587,000 67,537,000 77,251,000 86,570,000  60,204,000 71,837,000 78,048,000 87,317,000 94,386,000 58,788,000 67,855,000 79,563,000  55,355,000 62,544,000 68,809,000 73,799,000 78,319,000 86,458,000 92,351,000 97,550,000 58,841,000   
        current portion of long-term debt
        3,333,000                        
        ​
                                
        liabilities and stockholders’ (deficit) equity
                                
        stockholders’ (deficit) equity:
                                
        total stockholders’ (deficit) equity
           -6,272,000         -1,542,000            
        total liabilities and stockholders’ (deficit) equity
           53,016,000         51,333,000            
        prepaid expenses and other assets
            2,144,000 1,918,000 2,098,000 1,655,000 1,910,000 1,619,000 2,015,000 1,903,000 2,312,000 2,735,000 3,232,000 2,061,000 2,395,000 1,892,000 2,241,000 867,000 1,484,000 1,763,000 2,308,000 365,000 
        long‑term debt with related party
                     31,669,000 31,491,000 31,315,000 31,145,000 30,982,000 30,827,000 30,673,000 30,524,000 30,381,000 30,243,000 30,108,000 
        stockholders’ equity
                                
        right-of-use asset
                     1,339,000           
        accumulated other comprehensive loss
                     -5,000 -52,000 -43,000 -81,000 -82,000 -71,000 -17,000   -19,000  
        short-term investments
                             5,289,000 9,285,000  
        contingencies and commitments
                                
        accrued expenses
                             2,834,000 3,533,000 3,600,000 
        other current liabilities
                             9,000 9,000 1,008,000 
        liabilities, redeemable convertible preferred stock and stockholders’ equity
                                
        preferred stock warrant liability
                               1,644,000 
        redeemable convertible preferred stock
                                
        series a preferred stock: 22,501,174 shares previously authorized, no shares issued or outstanding at december 31, 2019 and 22,501,174 issued and outstanding at december 31, 2018
                                
        series b preferred stock: 82,891,619 shares previously authorized, no shares issued or outstanding at december 31, 2019 and 63,032,500 issued and outstanding at december 31, 2018
                                
        total redeemable convertible preferred stock
                               145,384,000 
        total liabilities, redeemable convertible preferred stock and stockholders’ equity
                              67,922,000  
        deferred offering costs
                               1,731,000 
        liabilities, redeemable convertible preferred stock, and stockholders’ deficit
                                
        series a preferred stock: 22,501,174 shares authorized, issued, and outstanding at september 30, 2019 and december 31, 2018; liquidation value of 34,458 at september 30, 2019
                               34,458,000 
        series b preferred stock: 82,891,619 shares authorized,75,560,456 and 63,032,500 issued and outstanding at september 30, 2019 and december 31, 2018, respectively; liquidation value of 110,213 at september 30, 2019
                               110,926,000 
        stockholders’ deficit:
                                
        total stockholders’ deficit
                               -160,400,000 
        total liabilities, redeemable convertible preferred stock and stockholders’ deficit
                               23,050,000 
      Cashflow Statements:
      Quarterly
      Annual
        Unit: USD2026-03-31 2025-12-31 2025-09-30 2025-06-30 2025-03-31 2024-12-31 2024-09-30 2024-06-30 2024-03-31 2023-12-31 2023-09-30 2023-06-30 2023-03-31 2022-12-31 2022-09-30 2022-06-30 2022-03-31 2021-12-31 2021-09-30 2021-06-30 2021-03-31 2020-12-31 2020-09-30 2020-06-30 2020-03-31 2019-12-31 
                                  
          cash flows from operating activities:
                                  
          net loss
        -12,273,000 -9,041,000 -8,603,000 -9,923,000 -11,264,000 -9,208,000 -10,372,000 -12,600,000 -5,661,000 -12,890,000 -10,957,000 -10,790,000 -12,027,000  -10,714,000 -12,741,000 -10,862,000  -8,266,000 -8,255,000 -8,136,000 -7,790,000 -7,703,000 -6,081,000 -7,220,000 -6,532,000 
          adjustments to reconcile net loss to net cash from operating activities:
                                  
          depreciation expense
        169,000 130,000 153,000 175,000 172,000 171,000 168,000 154,000 139,000 66,000 123,000 119,000 120,000 112,000 110,000 83,000 78,000 61,000 51,000 55,000 64,000 63,000 63,000 39,000 56,000 72,000 
          noncash interest expense
        238,000 159,000 110,000 109,000 151,000 154,000 153,000 151,000 151,000 152,000 151,000 149,000 147,000 150,000 148,000 181,000 178,000 176,000 170,000 162,000 156,000 154,000 149,000 147,000 134,000 128,000 
          amortization of intangible assets
        95,000 95,000 95,000 95,000 95,000 95,000 95,000 95,000 95,000 95,000 95,000 95,000 95,000 95,000 95,000 538,000 76,000 76,000 76,000 76,000 76,000 76,000 76,000 76,000 76,000 76,000 
          net changes in operating lease rou assets and liabilities
        -21,000 -21,000 375,000 -26,000 -26,000 -26,000 -26,000 -25,000 -22,000 -16,000 -11,000 -12,000 -10,000 -10,000 -9,000 -9,000 -8,000          
          inventory excess and obsolescence charge
        935,000 818,000 632,000 280,000 630,000 1,392,000 655,000 348,000 560,000 422,000 288,000 128,000 576,000 57,000 616,000 348,000 845,000 105,000 652,000 100,000 582,000 106,000 454,000 362,000 405,000 498,000 
          stock‑based compensation expense
        816,000 812,000 955,000 985,000 1,044,000 1,089,000 1,081,000 1,090,000 1,102,000 1,241,000 1,369,000 1,294,000 1,128,000 1,039,000 1,027,000 1,022,000 901,000 822,000 733,000 1,412,000 694,000 572,000 543,000 494,000 449,000 274,000 
          income tax expense
        60,000                          
          loss on disposal of fixed assets
        18,000                          
          change in operating assets and liabilities:
                                  
          accounts receivable
        593,000 932,000 -107,000 -533,000 -402,000 983,000 -2,008,000 497,000 -234,000 -1,602,000 -237,000 -1,201,000 -18,000 -890,000 -416,000 -1,030,000 -85,000 -657,000 -34,000 -750,000 -112,000 -41,000 -48,000 -543,000 781,000 -545,000 
          inventory
        -2,158,000 -275,000 -838,000 1,956,000 -1,346,000 -616,000 -811,000 -115,000 -1,430,000 785,000 -567,000 924,000 -3,860,000 467,000 -2,553,000 -482,000 -3,505,000 -1,493,000 -2,426,000 85,000 -1,360,000 44,000 86,000 -133,000 -617,000 -816,000 
          prepaid expenses and other current and long-term assets
        231,000                          
          accounts payable
        1,593,000 -63,000 652,000 -2,301,000 1,853,000 -154,000 42,000 -921,000 1,515,000 -1,524,000 884,000 -3,011,000 3,662,000 -3,175,000 2,702,000 -3,685,000 3,274,000 11,000 1,016,000 258,000 312,000 -327,000 421,000 -835,000 -1,261,000 1,697,000 
          accrued expenses and other current and long-term liabilities
        -1,498,000 663,000 633,000 1,394,000 -930,000 -842,000 1,660,000 847,000 -3,474,000 2,804,000 1,477,000 1,587,000 -1,691,000 1,600,000 583,000 2,136,000 -1,920,000 1,112,000         
          foreign currency transaction loss
        32,000 41,000 -48,000 17,000 66,000                      
          net cash from operating activities
        -11,170,000 -4,870,000 -5,719,000 -7,905,000 -9,725,000 -7,531,000 -8,983,000 -10,697,000 -14,384,000 -11,051,000 -6,968,000 -11,264,000 -11,574,000 -10,983,000 -7,649,000 -11,686,000 -10,430,000 -9,588,000 -6,630,000 -5,629,000 -8,585,000 -7,104,000 -3,690,000 -6,355,000 -7,307,000 -7,184,000 
          capital expenditures
        -119,000 -91,000 -211,000 -114,000 -32,000 -264,000 -122,000 -299,000 -304,000 -205,000 -134,000 -157,000 -115,000 -46,000 -290,000 -200,000 -336,000 -289,000 -291,000 -25,000 -22,000 -38,000 -33,000 -28,000 -68,000 
          free cash flows
        -11,289,000 -4,961,000 -5,930,000 -8,019,000 -9,757,000 -7,795,000 -9,105,000 -10,996,000 -14,688,000 -11,256,000 -7,102,000 -11,421,000 -11,689,000 -11,029,000 -7,939,000 -11,886,000 -10,766,000 -9,877,000 -6,921,000 -5,654,000 -8,607,000 -7,142,000 -3,723,000 -6,383,000 -7,375,000 -7,184,000 
          cash flows from investing activities:
                                  
          purchase of property and equipment
        -119,000 -91,000 -211,000 -114,000 -32,000 -264,000 -122,000 -299,000 -304,000 -205,000 -134,000 -157,000 -115,000 -46,000 -290,000 -200,000 -336,000 -289,000 -291,000 -25,000 -22,000 -38,000 -33,000 -28,000 -68,000  
          proceeds from the sale of product line
        309,000 283,000 523,000 318,000 170,000 74,000 366,000 5,000,000                  
          net cash from investing activities
        190,000 192,000 312,000 204,000 138,000 -190,000 -122,000 67,000 4,696,000 -193,000 -134,000 -157,000 -115,000 -1,046,000 -290,000 -200,000 -336,000 -289,000 -291,000 -25,000 -22,000 -38,000 -33,000 5,261,000 3,932,000 -9,317,000 
          cash flows from financing activities:
                                  
          payment of accrued offering costs
        -247,000                          
          vesting of restricted stock units
        1,000                          
          payment of withholding taxes related to stock-based compensation to employees
        -79,000 -4,000 -21,000 -3,000 -177,000 -11,000 -19,000 -11,000 -328,000 -4,000 -5,000 -1,000 -279,000 -4,000 -153,000          
          proceeds from issuance of common stock under the employee stock purchase plan
        27,000 45,000 60,000 117,000 164,000                 
          net cash from financing activities
        -298,000 25,845,000 24,000 -3,000 -116,000 42,908,000 98,000 -5,000 56,000 22,000 71,000 46,409,000 -235,000 -219,000 34,569,000 6,648,000 -146,000 174,000 259,000 116,000 36,000 46,000 -279,000 45,156,000 -514,000 51,105,000 
          effect of exchange rate on cash and cash equivalents
        -26,000 -35,000 104,000 -152,000 -134,000 182,000 -188,000 -12,000 46,000 14,000 -33,000 154,000 29,000 41,000 -129,000 -53,000 -3,000 -2,000 6,000 1,000 6,000      
          net decrease in cash and cash equivalents and restricted cash
        -11,304,000  -5,279,000 -7,856,000 -9,837,000    -9,586,000                  
          cash and cash equivalents and restricted cash, beginning of period
        51,095,000  52,935,000  46,994,000                  
          cash and cash equivalents and restricted cash, end of period
        39,791,000  -5,279,000 -7,856,000 43,098,000  -9,195,000 -10,647,000 37,408,000                  
          supplemental disclosure of cash flow information:
                                  
          cash paid during the period for interest
        1,815,000 738,000 1,311,000 1,297,000 1,370,000 519,000 1,191,000 1,180,000 1,181,000 1,193,000 1,183,000 1,149,000 1,099,000 1,024,000 884,000 753,000 733,000 746,000 752,000 702,000 733,000 749,000 749,000 737,000 745,000 756,000 
          noncash loss on extinguishment of debt
                                
          gain on disposal of fixed assets
                                  
          gain on sale of product line
             -7,580,000                  
          proceeds from the sale of property and equipment
                                  
          proceeds from sale of common stock and pre-funded warrants
                                  
          proceeds from issuance of long-term debt and warrants
                                  
          repayment of long-term debt
                                  
          payment of debt financing costs
                                 
          proceeds from exercise of stock options
         1,000 6,000 220,000 26,000 1,000 56,000 44,000 6,000 1,000 5,000 7,000 136,000 259,000 116,000 36,000 12,000 119,000 36,000 8,000 2,000 
          net increase in cash and cash equivalents and restricted cash
             35,369,000 -9,195,000                    
          cash and cash equivalents and restricted cash, beginning of year
                                  
          cash and cash equivalents and restricted cash, end of year
                                  
          supplemental disclosures of noncash investing and financing activities:
                                  
          property and equipment in accounts payable and accrued expenses and other current liabilities
         51,000 -11,000    120,000 -121,000 176,000 96,000 -26,000 31,000 18,000 -1,000             
          operating lease rou asset exchanged for operating lease liabilities
                     2,000 1,374,000          
          offering costs in accrued expenses and other current liabilities
                                  
          issuance of common stock warrants in connection with credit facility
                                  
          deferred income tax expense
          33,000 52,000                      
          prepaid expenses and other current assets
          272,000 -166,000 180,000 -297,000 271,000 -226,000 479,000 -442,000 254,000 -291,000 398,000              
          deferred income tax benefit
                                  
          payment for intangible asset
                                 
          proceeds from issuance of long-term debt
                                  
          tenant improvement and deferred rent reclassified to operating lease liabilities
                     380,000          
          operating lease liabilities assumed for operating lease rou assets
                     3,510,000 -1,754,000          
          foreign currency transaction gain
                                  
          proceeds from sale of common stock
                                  
          foreign currency translation loss
               8,000 -24,000                  
          proceeds from sale of common stock, net of underwriting discounts, commissions and offering costs
                 -13,000   -275,000             
          offering costs in accounts payable and accrued expenses and other current liabilities
                                  
          proceeds from the sale property and equipment
                                  
          proceeds from issuance of long‑term debt
                                
          repayment of long‑term debt
                                
          issuance of common stock for early exercised stock options
                             1,000 1,000 1,000 1,000 
          reclassification of liability-classified stock-based compensation awards to equity-classified
                                
          foreign currency remeasurement loss
                  163,000 -255,000 -94,000 -343,000 360,000 302,000 101,000 -12,000 41,000 -17,000  -38,000 7,000 38,000  
          net increase in cash and cash equivalents
                  -7,064,000   -12,207,000    -9,705,000 -6,656,000   -7,073,000 -4,004,000    
          cash and cash equivalents, beginning of period
                  42,019,000  43,931,000  74,394,000  45,302,000  
          cash and cash equivalents, end of period
                  -7,064,000 35,142,000 30,124,000  26,501,000 -5,291,000 33,016,000  -6,656,000 -5,537,000 65,829,000  -4,004,000 44,060,000 41,411,000  
          intangible asset in accrued expenses and other liabilities
                                 
          net decrease in cash and cash equivalents
                    -11,895,000   -5,291,000 -10,915,000    -8,565,000    -3,891,000  
          net income
                                  
          adjustments to reconcile net income to net cash from operating activities:
                                  
          proceeds from the sale and maturity of short-term investments
                             5,289,000 4,000,000  
          payment of initial public offering costs
                             -522,000  
          cash and cash equivalents, beginning of year
                                  
          cash and cash equivalents, end of year
                                  
          liability-classified stock-based compensation in accrued expenses and other current liabilities
                                  
          prepaid expenses and other assets
                      402,000 423,000 497,000 -1,172,000 334,000 -503,000 349,000 -1,374,000 617,000 279,000 544,000 -1,942,000 
          payment of financing costs
                                  
          property and equipment in accounts payable
                       130,000 16,000 69,000 42,000   -1,000     
          deferred financing costs in accounts payable and accrued expenses and other liabilities
                                  
          change in fair value of warrants
                                 1,000 
          purchases of short-term investments
                                  
          proceeds from follow-on offering, net of underwriting discounts, commissions and offering costs
                                  
          proceeds from initial public offering, net of underwriting discounts, commissions and offering costs
                                  
          proceeds from issuance of series b redeemable convertible preferred stock, net of offering costs
                                  
          accretion of redeemable convertible preferred stock
                                  
          conversion of convertible preferred stock to common stock in connection with the initial public offering
                                  
          conversion of outstanding preferred stock warrants
                                  
          unrealized loss on short-term investments
                                  
          accrued expenses and other current liabilities
                           1,731,000 -1,193,000      
          reclassification of liability-classified stock-based compensation to equity-classified
                            82,000      
          gain on sale of equipment
                                  
          restricted cash
                                  
          foreign currency remeasurement gain
                                  
          proceeds from issuance of long‑term debt with related party
                                  
          proceeds from issuance of long‑term debt and preferred stock warrants
                                  
          borrowings under revolving credit facility
                                  
          repayments of revolving credit facility
                                  
          payment of deferred financing costs
                                  
          effect of exchange rate on cash
                                  
          cash paid on loss on extinguishment of debt
                                  
          fair value of warrants issued in connection with equity and debt financing
                                  
          intangible assets in accrued expenses and other current liabilities
                                  
          recognition of exit fee for debt discount
                                  
          accrued expenses and other liabilities
                              1,690,000 -167,000 -692,000 -74,000 
          proceeds from underwritten public offering, net of underwriting discounts, commissions and offering costs
                              -398,000    
          offering costs in accounts payable and accrued expense and other current liabilities
                                  
          deferred series b equity costs in accounts payable and accrued expenses
                                  
          intangible assets in accrued expenses and other liabilities
                                  
          property and equipment purchases in accounts payable
                                4,000  
          beneficial conversion feature upon conversion of promissory notes
                                  
          loss on sale of property and equipment
                                  
          proceeds from sale of property and equipment
                                  
          proceeds from initial public offering net of underwriting discounts, commissions and offering costs
                                  
          proceeds from issuance of convertible promissory notes and preferred stock warrants
                                  
          payment of capital lease obligations
                                  
          offering costs in accounts payable
                                  
          conversion of convertible promissory notes and accrued interest to series b redeemable convertible preferred stock
                                  
          changes in operating assets and liabilities:
                                  
          purchases of property and equipment
                                  
          proceeds from issuance of series b redeemable preferred stock
                                  
          accretion of redeemable preferred stock to redemption value
                                  
          deferred offering costs in accounts payable and accrued expenses